Diagnostic Trouble Code (DTC) P064C, P0670, P0671, P0672, P0673, P0674, P0683, P161E
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P064C (00): Glow Plug Control Module Performance
DTC P0670 (01): Glow Plug Control Module Control Circuit (Short to Battery)
DTC P0670 (02): Glow Plug Control Module Control Circuit (Short to Ground)
DTC P0670 (04): Glow Plug Control Module Control Circuit (Open Circuit)
DTC P0670 (54): Glow Plug Control Module Control Circuit (Temperature High)
DTC P0671 (02): Glow Plug 1 Control Circuit (Short to Ground)
DTC P0671 (04): Glow Plug 1 Control Circuit (Open Circuit)
DTC P0672 (02): Glow Plug 2 Control Circuit (Short to Ground)
DTC P0672 (04): Glow Plug 2 Control Circuit (Open Circuit)
DTC P0673 (02): Glow Plug 3 Control Circuit (Short to Ground)
DTC P0673 (04): Glow Plug 3 Control Circuit (Open Circuit)
DTC P0674 (02): Glow Plug 4 Control Circuit (Short to Ground)
DTC P0674 (04): Glow Plug 4 Control Circuit (Open Circuit)
DTC P0683 (00): Glow Plug Control Module Communication Circuit
DTC P0683 (3A): Glow Plug Control Module Communication Circuit (Incorrect Component Installed)
DTC P0683 (71): Glow Plug Control Module Communication Circuit (Invalid Serial Data Received)
DTC P161E (00): Glow Plug Positive Voltage Circuit
Circuit/System Description
The glow plug control unit has the ability to perform internal diagnostics for voltage and output state of the glow plugs. If the glow plug control unit senses an open in the voltage supply to the glow plug control unit, or a condition with any of the glow plug driver circuits, the glow plug control unit will send an error message to the engine control module (ECM).
Conditions for Running the DTC
P064C(00), P0671(02), P0671(04), P0672(02), P0672(04), P0673(02), P0673(04), P0674(02), P0674(04), P0683(00), P0683(3A), P0683(71), and P161E(00)
- Ignition switch is ON
- Battery voltage is between 8.5V and 16.5V
P0670(01) and P0670(54)
- The glow plug control unit control circuit power stage is energized
- Ignition switch is ON
- Battery voltage is between 8.5V and 16.5V
P0670(02) and P0670(04)
- The glow plug control unit control circuit power stage is switched off
- Ignition switch is ON
- Battery voltage is between 8.5V and 16.5V
Conditions for Setting the DTC
P064C(00)
- ECM detects the glow plug control unit malfunction
P0670(01)
- A short to battery condition exists in the glow plug control unit control circuit
P0670(02)
- A short to ground condition exists in the glow plug control unit control circuit
P0670(04)
- An open condition exists in the glow plug control unit control circuit
P0670(54)
- A high temperature condition exists in the glow plug control unit control circuit
P0671(02), P0672(02), P0673(02), and P0674(02)
- A short circuit or a over current condition exists in the glow plug control circuit
P0671(04), P0672(04), P0673(04), and P0674(04)
- A harness defect or open exists in the glow plug 1 control circuit or the glow plug 1 is defective
P0683(00)
- ECM detects that the glow plug control unit is sending faulty diagnosis transmission or protocol error
P0683(3A)
- ECM detects no communication with GCU
P0683(71)
- ECM detects that 3 different communication words were received from GCU
P161E(00)
- ECM detects no voltage in the glow plug positive voltage circuit
Action Taken When the DTC Sets
- DTC P064C, P0670, P0671, P0672, P0673, P0674, P0683, and P161E are type Cnl DTCs.
Conditions for Clearing the MIL/DTC
- DTC P064C, P0670, P0671, P0672, P0673, P0674, P0683, and P161E are type Cnl DTCs.
DTC P064C, P0670, P0671, P0672, P0673, P0674, P0683, P161E
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | Is the DTC P064C or P161E set? | - | Go to Step 9 | Go to Step 3 |
| 3 | - Observe the Freeze Frame/Failure Records for this DTC.
- Turn OFF the ignition.
- Turn ON the ignition, with the engine OFF.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 4 | |
| 4 | - Turn ON the ignition, with the engine OFF.
- Probe the terminal on the affected glow plug, with a test lamp connected to the ground.
- Command the glow plugs ON, with a scan tool.
Does the test lamp illuminate with the glow plugs commanded ON? | - | Go to Step 6 | Go to Step 5 |
| 5 | Important : - If a glow plug control circuit is shorted to 12 volts, the glow plug will be damaged and the glow plug must be replaced.
- If a glow plug is replaced and the tip is missing or burned off, the cylinder head must be removed and all debris must be cleaned out of the cylinder.
Test the affected glow plug control circuit between the glow plug control unit and the glow plug for the following conditions: - An open
- A short to ground
- A short to voltage
Did you find and correct the condition? | - | Go to Step 18 | Go to Step 9 |
| 6 | - Turn OFF the ignition.
- Disconnect the glow plug connector at the affected glow plugs.
- Probe the terminal on the glow plug with a test lamp connected to battery voltage.
Does the test lamp illuminate? | - | Go to Step 7 | Go to Step 15 |
| 7 | Measure the resistance between the affected glow plug terminal and a good ground on the engine with a DMM. Does the DMM display a resistance less than the specified value? | 1 ohm | Go to Step 8 | Go to Step 15 |
| 8 | - Disconnect the wiring harness connector from the glow plug control unit.
- Measure the resistance of the affected glow plug control circuit between the glow plug harness connector and the glow plug control unit with a DMM.
Does the DMM display a resistance less than the specified value? | 1 ohm | Go to Step 16 | Go to Step 12 |
| 9 | - Turn OFF the ignition.
- Disconnect the wiring harness connector from the glow plug control unit.
- Probe the battery voltage supply circuit with a test lamp connected to a good ground.
Does the test lamp illuminate? | - | Go to Step 10 | Go to Step 14 |
| 10 | - Turn OFF the ignition.
- Disconnect the harness connector from the glow plug control unit.
- Measure the resistance between the ground circuit and a good ground with a DMM.
Does the DMM display a resistance below the specified value? | - | Go to Step 11 | Go to Step 13 |
| 11 | Test for an intermittent and for a poor connection at the harness connector of the glow plug control unit. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 16 |
| 12 | Repair or replace the glow plug harness. Did you complete the repair? | - | Go to Step 18 | - |
| 13 | Repair the high resistance in the ground circuit of the glow plug control circuit. Did you complete the repair? | - | Go to Step 15 | - |
| 14 | Repair the open or the short to ground in the battery voltage supply circuit. Did you complete the repair? | - | Go to Step 18 | - |
| 15 | Important : If a glow plug is replaced and the tip is missing or burned off, the cylinder head must be removed and all debris must be cleaned out of the cylinder. Replace the glow plug. Did you complete the replacement? | - | Go to Step 18 | - |
| 16 | - Replace the glow plug control unit.
- Operate the vehicle within the Conditions for Running the DTC.
- Observe the DTC information with a scan tool.
Did the DTC fail this ignition? | - | Go to Step 17 | Go to Step 18 |
| 17 | Replace the ECM. Did you complete the replacement? | - | Go to Step 18 | - |
| 18 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 19 |
| 19 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0700
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P0700 (00): Transmission Control Module (TCM) Requested MIL Illumination
Circuit/System Description
This diagnostic trouble code (DTC) indicates that an emission related transmission DTC set in the transmission control module (TCM). The engine control module (ECM) receives the TCM information over the serial data circuit. The ECM turns ON the malfunction indicator lamp (MIL) when the TCM sends a message over the serial data circuit requesting MIL illumination. The DTC information for the ECM will only display DTC P0700.
Conditions for Running the DTC
Conditions for Setting the DTC
- The ECM detects that the transmission control module (TCM) requested MIL illumination
Action Taken When the DTC Sets
Conditions for Clearing the MIL/DTC
DTC P0700
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Install a scan tool to the Data Link Connector (DLC).
- Turn the ignition ON.
- Select Transaxle Control Module (TCM) Diagnostic Trouble Code (DTC) with scan tool.
Is a transmission DTC displayed? | - | Go to Step 3 | Go to Step 4 |
| 3 | - Repair transaxle malfunction. Refer to the applicable DTC table in the transmission repair section.
- Using a scan tool, clear the TCM DTC.
Is the repair complete? | - | Go to Step 4 | - |
| 4 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 5 |
| 5 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0850
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P0850 (02): Park/Neutral Position (PNP) Switch Circuit (Short to Ground)
DTC P0850 (05): Park/Neutral Position (PNP) Switch Circuit (Short to Battery or Open)
Circuit/System Description
When the transmission is in Park or Neutral, the switch closes. The ECM uses the switch in order to enable starter operation.
Conditions for Running the DTC
Conditions for Setting the DTC
P0850(02)
- The ECM detects that the PNP switch reports other than P/N position while the select lever status indicates P/N
P0850(05)
- The ECM detects that the PNP switch reports P/N position while the select lever status does not indicate P/N
Action Taken When the DTC Sets
- DTC P0850 is type Cnl DTC.
Conditions for Clearing the MIL/DTC
- DTC P0850 is type Cnl DTC.
Diagnostic Aids
- For an intermittent condition, refer to "Intermittent Conditions".
- Since fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic procedure for shorted terminals or poor wiring connection before replacing any component.
DTC P0850
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | Test the PNP switch signal circuit for an open or for a high resistance between the PNP switch and the engine control module (ECM). Did you find and correct the condition? | - | Go to Step 5 | Go to Step 3 |
| 3 | Inspect for poor connections at the harness connector of the ECM. Did you find and correct the condition? | - | Go to Step 5 | Go to Step 4 |
| 4 | Replace the ECM. Did you complete the replacement? | - | Go to Step 5 | - |
| 5 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 6 |
| 6 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P0856
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P0856 (72): Traction Control Torque Request Circuit (Alive Counter Incorrect/Not Updated)
DTC P0856 (74): Traction Control Torque Request Circuit (Value of Signal Protection Calculation Incorrect)
Circuit/System Description
The electronic brake control module (EBCM) and the engine control module (ECM) simultaneously control the traction control. The ECM reduces the amount of torque supplied to the drive wheels and the EBCM actively applies the brakes to the front wheels in order to reduce torque. The EBCM sends a GMLAN serial data message to the engine control module (ECM) indicating the function that has been requested.
Conditions for Running the DTC
Conditions for Setting the DTC
P0856(72)
- The ECM detects that the total number of protection value error is greater than 5
P0856(74)
- The ECM detects that the total number of rolling count error is greater than 3
Action Taken When the DTC Sets
- DTC P0856 is type Cnl DTC.
Conditions for Clearing the MIL/DTC
- DTC P0856 is type Cnl DTC.
Diagnostic Aids
This DTC may be stored as a history DTC without affecting the operation of the EBCM. If stored only as a history DTC and not retrieved as a current DTC, do not replace the BCM. If this DTC is retrieved as both a current and history DTC, replace the EBCM.
DTC P0856
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | Is DTC P0856 current in the engine control module (ECM)? | - | Go to Step 3 | Go to Diagnostic Aids |
| 3 | Replace the EBCM. Did you complete the replacement? | - | Go to Step 4 | - |
| 4 | - Use the scan tool in order to clear the DTCs.
- Operate the vehicle within the Conditions for Running the DTC.
Does the DTC reset? | - | Go to Step 2 | System OK |
Diagnostic Trouble Code (DTC) P1446, P1447, P244C, P244D
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P1446 (00): Pre-Catalyst Temperature Too Low During Regeneration
DTC P1447 (00): Pre-Catalyst Temperature Too High During Regeneration
DTC P244C (00): Catalyst Temperature Too Low During Regeneration
DTC P244D (00): Catalyst Temperature Too High During Regeneration
Circuit/System Description
The diesel after-treatment system consists of an under hood pre-catalytic converter and an underbody catalytic converter. The underbody catalytic converter also consists of the main Diesel Oxidation Catalyst (DOC) and the coated Diesel Particulate Filter (DPF).
The DPF is made of Silicon Carbide and is coated with noble metal. One of the main purposes of the DPF is to collect particulates from the engine exhaust in order to minimize discharge of soot to the atmosphere.
The soot particles accumulate in the channels of the coated diesel filter and are burned off at regular interval through a process called ‘regeneration’. This prevents the filter from clogging. The ECM commands the DPF regeneration after calculating the various vehicle conditions such as DPF pressure difference, exhaust gas temperature, engine oil quality, engine speed, etc. Excessive accumulation of the soot in the DPF can cause a drop in the engine performance and lead to crack of the filter during regeneration.
During regeneration, additional fuel is injected via multiple post injections in order to increase the exhaust gas temperature. During this period, the DPF temperature is raised to approximately 600°C and the accumulated soot is oxidized or burned off into carbon-dioxide (CO2).
The pressure pipes, which are connected to the DPF pressure difference sensor, measure the level of soot deposit in the DPF and protect the engine by triggering regeneration when critical soot level is detected in the filter.
Conditions for Running the DTC
- Vehicle is under DPF regeneration process
Conditions for Setting the DTC
P1446(00)
- Measured temperature of upstream of pre-catalyst (EGT1) is less than desired temperature by 200°C or greater
P1447(00)
- Measured temperature of upstream of pre-catalyst (EGT1) is greater than desired temperature by 100°C or greater
P244C(00)
- Measured temperature of upstream of DPF (EGT2) is less than desired temperature by 125°C or greater
P244D(00)
- Measured temperature of upstream of DPF (EGT2) is greater than desired temperature by 150°C or greater
Action Taken When the DTC Sets
- DTC P1446, P1447, P244C, and P244D are type A DTCs.
Conditions for Clearing the MIL/DTC
- DTC P1446, P1447, P244C, and P244D are type A DTCs.
DTC P1446, P1447, P244C, P244D
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | Using a scan tool, observe the DTC information. Are any other DTCs set other than P1446, P1447, P244C, and P244D? | - | Go to applicable DTC table | Go to Step 3 |
| 3 | Inspect the proper operation of the following sensors and components: - Exhaust gas temperature sensor 1, 2
- Mass air flow (MAF) sensor
- Throttle plate actuator
- Crankshaft position (CKP) sensor
- Camshaft position (CMP) sensor
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 4 |
| 4 | Inspect the EGR system for the followings: - Stuck open or stuck closed
- Incorrect EGR position
- Wiring harness
Did you find and correct the condition | - | Go to Step 11 | Go to Step 5 |
| 5 | Inspect for air leaks in the following components: - The air induction system and the turbocharger system
- The charge air cooler
- The mass air flow (MAF)/intake air temperature (IAT) sensor O-ring seal
- The boost pressure sensor seal
- An exhaust gas recirculation (EGR) valve gasket that is missing or damaged
- The throttle body gasket that is missing or damaged
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 6 |
| 6 | Inspect the fuel filter and low pressure fuel lines for the followings: - Proper filter installed
- Excessive water in the fuel filter housing
- Fuel heater, fuel temperature sensor, or water in fuel sensor failure, or wiring harness condition
- Fuel filter for clogging
- Fuel leakage
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 7 |
| 7 | Inspect the injectors for the followings: - Wearing of injectors
- Corrosion by water in fuel
- Incorrect IQA
- Wiring harness
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 8 |
| 8 | Inspect the high pressure fuel system for the followings: - Wiring harness
- Impaired lubrication by poor fuel quality
- Crack or leakage in the common rail, fuel pipes, FRP regulator, FPR sensor, fittings, etc.
- Damaged fuel injection pump
- Fuel injection pump timing misaligned
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 9 |
| 9 | Inspect the turbocharger system for the followings: - Turbocharger vane stuck
- Boost pressure actuator failure
- Damaged compressor wheel
- Damaged bearings
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 10 |
| 10 | Inspect the proper operations for the following base engine components: - Valve train
- Valve stem seal
- Piston / piston ring
- Crack in the oil galleries
- Oil dilution by high fuel consumption
Did you find and correct the condition? | - | Go to Step 11 | Go to Step 2 |
| 11 | - Clear the DTCs with the scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 12 |
| 12 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P1629, P1631, P1632
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P1629 (00): Theft Deterrent Fuel Enable Signal Not Received
DTC P1631 (00): Theft Deterrent Fuel Enable Signal Not Correct
DTC P1632 (00): Theft Deterrent Fuel Disable Signal Received
Circuit/System Description
The immobilizer module or the vehicle theft deterrent (VTD) module sends the fuel enable password to the engine control module (ECM) via the serial data circuit. The ECM then challenges this password. Both the ECM and immobilizer module perform a calculation on this challenge. If the calculated response from the immobilizer module equals the calculation performed by the ECM, the ECM will allow vehicle starting. The ECM will disable vehicle starting if any of the following conditions occur:
- The fuel enable password is invalid.
- The fuel disable password is sent by the immobilizer module.
- No passwords are received. - There is no communication with the immobilizer module.
- The immobilizer module calculated response to the challenge does not equal the calculation performed by the ECM.
Conditions for Running the DTC
- Ignition switch is ON
- Immobilizer function is activated
Conditions for Setting the DTC
P1629(00)
- The immobilizer state is immobilized due to no response
P1631(00)
- The Immobilizer has not released the engine
- Authentication status is not VALID
- The ECU has received an incorrect pre release password
P1632(00)
- The immobilizer state is immobilized due to negative response
Action Taken When the DTC Sets
- DTC P1629, P1631, and P1632 are type Cnl DTCs.
Conditions for Clearing the MIL/DTC
- DTC P1629, P1631, and P1632 are type Cnl DTCs.
DTC P1629, P1631, P1632
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Turn the ignition switch to LOCK.
- Install a scan tool to the data link connector (DLC).
- Turn the ignition switch to ON.
- Check if other immobilizer related DTCs are set.
Are any DTCs displayed? | - | Go to Applicable DTC table | Go to Step 3 |
| 3 | Is the programming complete successfully? | - | Go to Step 5 | Go to Step 4 |
| 4 | Replace the ECM. Is the replace complete? | - | Go to Step 5 | - |
| 5 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 6 |
| 6 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2002, P244B, P2452, P2453, P2458, P2463
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P2002 (00): Diesel Particulate Filter Low Efficiency
DTC P244B (11): Diesel Particulate Filter Differential Pressure Too High (Above Maximum Threshold)
DTC P2452 (03): Diesel Particulate Filter Differential Pressure Sensor Circuit (Voltage Below Threshold)
DTC P2452 (07): Diesel Particulate Filter Differential Pressure Sensor Circuit (Voltage Above Threshold)
DTC P2453 (00): Diesel Particulate Filter Differential Pressure Sensor Performance
DTC P2453 (08): Diesel Particulate Filter Differential Pressure Sensor Performance (Signal Invalid)
DTC P2453 (11): Diesel Particulate Filter Differential Pressure Sensor Performance (Above Maximum Threshold)
DTC P2453 (12): Diesel Particulate Filter Differential Pressure Sensor Performance (Below Minimum Threshold)
DTC P2453 (18): Diesel Particulate Filter Differential Pressure Sensor Performance (Signal Amplitude Less Than Minimum)
DTC P2453 (55): Diesel Particulate Filter Differential Pressure Sensor Performance (Expected Number of Transitions/Events Not Reached)
DTC P2453 (58): Diesel Particulate Filter Differential Pressure Sensor Performance (Incorrect Reaction After Event)
DTC P2458 (59): Diesel Particulate Filter Regeneration Time (Circuit/Component Protection Time-Out)
DTC P2463 (00): Diesel Particulate Filter Soot Accumulation
DTC P2463 (11): Diesel Particulate Filter Soot Accumulation (Above Maximum Threshold)
Circuit/System Description
The diesel after-treatment system consists of an under hood pre-catalytic converter and an underbody catalytic converter. The underbody catalytic converter also consists of the main Diesel Oxidation Catalyst (DOC) and the coated Diesel Particulate Filter (DPF).
The DPF is made of Silicon Carbide and is coated with noble metal. One of the main purposes of the DPF is to collect particulates from the engine exhaust in order to minimize discharge of soot to the atmosphere.
The soot particles accumulate in the channels of the coated diesel filter and are burned off at regular interval through a process called ‘regeneration’. This prevents the filter from clogging. The ECM commands the DPF regeneration after calculating the various vehicle conditions such as DPF pressure difference, exhaust gas temperature, engine oil quality, engine speed, etc. Excessive accumulation of the soot in the DPF can cause a drop in the engine performance and lead to crack of the filter during regeneration.
During regeneration, additional fuel is injected via multiple post injections in order to increase the exhaust gas temperature. During this period, the DPF temperature is raised to approximately 600°C and the accumulated soot is oxidized or burned off into carbon-dioxide (CO2).
The pressure pipes, which are connected to the DPF pressure difference sensor, measure the level of soot deposit in the DPF and protect the engine by triggering regeneration when critical soot level is detected in the filter.
Conditions for Running the DTC
P2002(00), P244B(11), P2452(03), P2452(07), P2453(11), P2453(12), P2453(55), P2453(58), P2453(08), P2458(59), P2463(00), and P2463(11)
P2453(00) and P2453(18)
- Ignition switch is ON
- The engine is in afterrun after engine standstill
Conditions for Setting the DTC
P2002(00)
- ECM detects that the pressure difference of the DPF is less than 9 hPa
P244B(11)
- The ECM detects that the pressure upstream of the DPF exceeds the maximum permissible pressure
P2452(03)
- Diesel particulate filter (DPF) differential pressure sensor raw signal voltage is less than 200mV
P2452(07)
- Diesel particulate filter (DPF) differential pressure sensor raw signal voltage is greater than 4721mV
P2453(00)
- The ECM detects that the absolute value of the raw differential pressure signal is greater than 41hPa, OR
- The ECM detects that the difference between the absolute pressure upstream of the particle filter and atmospheric pressure is greater than 1200hPa
P2453(11)
- The ECM detects that the raw differential pressure signal is greater than 900hPa
P2453(12)
- The ECM detects that the raw differential pressure signal is less than -40hPa
P2453(18)
- The minimum of the differential pressure is lower than the threshold
P2453(55)
- The ECM detects that the filtered differential pressure signal is less than -10hPa
P2453(58)
- The ECM detects that the induction temperature is less than 0°C
P2453(08)
- The change of the differential pressure is less than the positive minimum value
P2458(59)
- The ECM detects that the regeneration demand exists after the maximum regeneration time has passed
P2463(00)
- The ECM detects that the particulate mass in the DPF is greater than 50g
P2463(11)
- The ECM detects that the particulate mass is greater than 50g
Action Taken When the DTC Sets
- DTC P2002, P2453(08), P2453(18), P2453(55), and P2458 are type E DTCs.
- DTC P244B, P2452, P2453(00), P2453(11), P2453(12), and P2463 are type A DTCs
- DTC P2453(58) is type Cnl DTC.
Conditions for Clearing the MIL/DTC
- DTC P2002, P2453(08), P2453(18), P2453(55), and P2458 are type E DTCs.
- DTC P244B, P2452, P2453(00), P2453(11), P2453(12), and P2463 are type A DTCs.
- DTC P2453(58) is type Cnl DTC.
Diagnostic Aids
- For an intermittent fault condition, refer to "Intermittent Conditions".
- Inspect the sensor for an incorrectly routed harness or if the harness is too close to the following:
- solenoids,
- relays, and
- motors.
- Since fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic procedure for shorted terminals or poor wiring connection before replacing any component.
DTC P2002, P244B, P2452, P2453, P2458, P2463
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | Check if one or more of the conditions are met for the DPF service regeneration. Refer to ‘Setup for Component Replacement’ in ENGINE CONTROL MODULE PROGRAMMING AND SETUP (Z20S DIESEL ENGINE) Does the DPF system require service regeneration? | - | Refer to ‘DPF Service Regeneration’ | Go to Step 3 |
| 3 | Check for any leakage and/or blockage in the following components: - Exhaust system
- Catalytic converter
- Diesel particulate filter (DPF)
- Exhaust gas temperature sensor 1, 2
- DPF pressure difference sensor
Note : Check the hoses for leakage or blockage before replacing the component Did you find and correct the condition? | - | Go to Step 14 | Go to Step 4 |
| 4 | - Turn the ignition ON.
- Observe the scan tool DTC information.
Did the DTC P2453(0) set? | - | Go to Step 12 | Go to Step 5 |
| 5 | - Turn the ignition OFF.
- Disconnect the wiring harness connector from the DPF pressure difference sensor.
- Turn the ignition ON.
- Using a DMM, measure the voltage between the 5V reference circuit and the low reference circuit of the DPF pressure difference sensor.
Is the voltage between the specified values? | 4.8 - 5.2 V | Go to Step 6 | Go to Step 7 |
| 6 | - Turn the ignition ON.
- Observe the DPF pressure difference sensor parameter with a scan tool.
Is the parameter less than the specified value? | 0.3 V | Go to Step 8 | Go to Step 9 |
| 7 | Using a DMM, measure the voltage between the 5V reference circuit of the DPF pressure difference sensor and a good ground. Is the voltage between the specified values? | 4.8 - 5.2 V | Go to Step 10 | Go to Step 11 |
| 8 | Check the DPF pressure difference sensor signal circuit for the following conditions: - Short to ground
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 14 | Go to Step 12 |
| 9 | Check the DPF pressure difference sensor signal circuit for short to voltage. Did you find and correct the condition? | - | Go to Step 14 | Go to Step 13 |
| 10 | Check the DPF pressure difference sensor low reference circuit for the following conditions: - Short to voltage
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 14 | Go to Step 13 |
| 11 | Check the DPF pressure difference sensor 5V reference circuit for the following conditions: - Short to voltage
- Short to ground
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 14 | Go to Step 13 |
| 12 | Replace the DPF pressure difference sensor. Did you complete the replacement? | - | Go to Step 14 | - |
| 13 | Replace the ECM. Did you complete the replacement? | - | Go to Step 14 | - |
| 14 | - Clear the DTCs with the scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 15 |
| 15 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2120, P2125, P2138, P2299
DTC Description
Note : The symptom byte may not be displayed on a scan tool.
DTC P2120 (03): Accelerator Pedal Position (APP) Sensor 1 Circuit (Voltage Below Threshold)
DTC P2120 (07): Accelerator Pedal Position (APP) Sensor 1 Circuit (Voltage Above Threshold)
DTC P2125 (03): Accelerator Pedal Position (APP) Sensor 2 Circuit (Voltage Below Threshold)
DTC P2125 (07): Accelerator Pedal Position (APP) Sensor 2 Circuit (Voltage Above Threshold)
DTC P2138 (5A): Accelerator Pedal Position (APP) Sensor 1-2 Correlation (Plausibility Failure)
DTC P2299 (5A): Brake Pedal Position-Accelerator Pedal Position Correlation (Plausibility Failure)
Circuit/System Description
The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted in the pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to the position of the accelerator pedal. The engine control module (ECM) supplies a separate 5-volt reference and low reference circuit for each of the APP sensors.
The APP sensor 1 signal voltage increases as the pedal is depressed, from approximately 1 volt at rest to above 4 volts when fully depressed. The APP sensor 2 signal voltage increases as the pedal is depressed, from approximately 0.5 volts at rest to more than 2 volts with the accelerator pedal fully depressed.
Conditions for Running the DTC
Conditions for Setting the DTC
P2120(03)
- APP 1 sensor raw signal voltage is less than 596mV
P2120(07)
- APP 1 sensor raw signal voltage is greater than 4624mV
P2125(03)
- APP 2 sensor raw signal voltage is less than 288mV
P2125(07)
- APP 2 sensor raw signal voltage is greater than 2326mV
P2138(5A)
- Difference between APP 1 signal and APP 2 signal is greater than expected
P2299(5A)
- ECM detects that the accelerator pedal and the brake were actuated simultaneously or the accelerator pedal was actuated before the brake.
Action Taken When the DTC Sets
- DTC P2120, P2125, and P2138 are type Cnl DTCs.
- DTC P2299 is type E DTC.
Conditions for Clearing the MIL/DTC
- DTC P2120, P2125, and P2138 are type Cnl DTCs.
- DTC P2299 is type E DTC.
Diagnostic Aids
- For an intermittent fault condition, refer to "Intermittent Conditions"
- Since fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic procedure for shorted terminals or poor wiring connection before replacing any component.
DTC P2120, P2125, P2138, P2299
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Turn the ignition OFF.
- Disconnect the wiring harness connector from the APP sensor.
- Turn the ignition ON.
- Using a DMM, measure the voltage between the 5V reference circuit of the APP sensor 1 and a good ground.
Is the voltage within the specified value? | 4.8 - 5.2 V | Go to Step 3 | Go to Step 10 |
| 3 | Using a DMM, measure the voltage between the 5V reference circuit and the low reference circuit of the APP sensor 1. Is the voltage within the specified value? | 4.8 - 5.2 V | Go to Step 4 | Go to Step 11 |
| 4 | - Turn the ignition ON, with the engine OFF.
- With a scan tool, observe the APP sensor 1 parameter.
Does the scan tool indicate that the APP sensor parameter is less than the specified value? | 0.3 V | Go to Step 5 | Go to Step 12 |
| 5 | - Turn the ignition OFF.
- Connect a fused jumper wire between the 5V reference circuit and the signal circuit of the APP sensor 1.
- Turn the ignition ON, with the engine OFF.
- With a scan tool, observe the APP sensor 1 parameter.
Does the scan tool indicate that the APP sensor parameter is within the specified value? | 4.8 - 5.2 V | Go to Step 6 | Go to Step 13 |
| 6 | - Turn OFF the ignition.
- Remove the fused jumper wire.
- Using a DMM, measure the voltage between the 5V reference circuit of the APP sensor 2 and a good ground.
Is the voltage within the specified value? | 4.8 - 5.2 V | Go to Step 7 | Go to Step 14 |
| 7 | Using a DMM, measure the voltage between the 5V reference circuit and the low reference circuit of the APP sensor 2. Is the voltage within the specified value? | 4.8 - 5.2 V | Go to Step 8 | Go to Step 15 |
| 8 | - Turn the ignition ON, with the engine OFF.
- With a scan tool, observe the APP sensor 2 parameter.
Does the scan tool indicate that the APP sensor parameter is less than the specified value? | 0.3 V | Go to Step 9 | Go to Step 16 |
| 9 | - Turn the ignition OFF.
- Connect a fused jumper wire between the 5V reference circuit and the signal circuit of the APP sensor 2.
- Turn the ignition ON, with the engine OFF.
- With a scan tool, observe the APP sensor 2 parameter.
Does the scan tool indicate that the APP sensor parameter is within the specified value? | 4.8 - 5.2 V | Go to Step 18 | Go to Step 17 |
| 10 | Check the APP sensor 1 5V reference circuit for the following conditions: - Short to voltage
- Short to ground
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 11 | Check the APP sensor 1 low reference circuit for the following conditions: - Short to voltage
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 12 | Check the APP sensor 1 signal circuit for the following condition: Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 13 | Check the APP sensor 1 signal circuit for the following conditions: - Short to ground
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 14 | Check the APP sensor 2 5V reference circuit for the following conditions: - Short to voltage
- Short to ground
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 15 | Check the APP sensor 2 low reference circuit for the following conditions: - Short to voltage
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 16 | Check the APP sensor 2 signal circuit for the following condition: Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 17 | Check the APP sensor 2 signal circuit for the following conditions: - Short to ground
- Open
- High resistance
Did you find and correct the condition? | - | Go to Step 20 | Go to Step 19 |
| 18 | Note : The APP sensor is not serviceable. Replace the accelerator pedal assembly. Did you complete the replacement? | - | Go to Step 20 | - |
| 19 | Replace the ECM. Did you complete the replacement? | - | Go to Step 20 | - |
| 20 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 21 |
| 21 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
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