Diagnostic Trouble Code (DTC) P0700
Transaxle Control Module (TCM) Requested Mil Illumination
Circuit Description
The Transaxle Control Module (TCM) and the Engine Control Module (ECM) are connected through the serial data link circuit. The TCM sends a P-code status message to the ECM every 100 milliseconds to confirm the transmission is functioning correctly.
If the TCM detects a malfunction within the transmission, the TCM will send to the ECM a P-code status message to turn the Malfunction Indicator Lamp (MIL) ON and set DTC P0700.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed-through wire insulation or a wire broken inside the insulation.
Check for a poor connection or damaged ECM/TCM harness. Inspect the serial data link circuit for the following conditions:
- Improper mating
- Broken locks
- Improperly formed
- Damaged terminals
- Poor terminal-to-wiring connections
- Damaged harness
DTC P0700 - Transaxle Control Module (TCM) Requested Mil Illumination
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Was the check performed? | - | 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 | - Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the Conditions for setting this DTC as specified in the supporting text.
Does the scan tool indicate that this diagnostic has run and passed? | - | Go to Step 5 | Go to Step 2 |
| 5 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC Table | System OK |
Diagnostic Trouble Code (DTC) P0703
Brake Switch Circuit 2
Circuit Description
Brake switch information is sent to the transmission control module (TCM) by the engine control module (BCM) through a communication network called the controller area network (CAN). Two circuits are used to communicate CAN data between the ECM and TCM. A fault in the CAN will not cause DTC P0703 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P0703.
Conditions for Running the DTC
Conditions for Setting the DTC
- Brake switch active and vehicle speed is greater than 90 km/h.
- Brake light switch is not active when the brake switch active for 20 seconds.
- Vehicle deceleration without brake switch active for 4 seconds.
Action Taken When the DTC Sets
- The Service Vehicle Soon (SVS) Lamp will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the disgnostic fails. This information will be stored in Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The SVS lamp will turn off after current driving cycle in which the disgnostic runs without a fault.
- A history DTC will clear after 20 consecutive warm-up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 secponds.
DTC P0703 - Brake Switch Circuit 2
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Install a scan tool.
- Turn the ignition ON, with the engine OFF.
- Record the DTC Failure Records.
Did you record any ECM Failure Records? | - | - | Go to Step 3 |
| 3 | - Clear the DTC.
- Turn the ignition OFF for at least 30 seconds.
- Start, and allow the engine to idle.
Did the DTC 0703 fail this ignition? | - | Go to Step 4 | - |
| 4 | Did any other DTCs set? | - | Go to Step 5 | - |
| 5 | Replace the ECM. Did you complete the replacement? | - | Go to Step 6 | - |
| 6 | - 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 7 |
| 7 | 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) P0833
Clutch Pedal Switch 2 Circuit
Circuit Description
The clutch switch is a normally closed switch, clutch pedal released. The engine control module (ECM) detects an ignition voltage on the clutch switch circuit when the clutch switch is closed. The ECM detects 0 volts on the clutch switch circuit when the clutch switch is open, clutch pedal depressed. When the ECM detects a large number of gear changes without detecting a clutch switch transition, DTC P0833 sets.
Conditions for Running the DTC
- No brake operation.
- Vehicle speed is greater than 50 km/h.
Conditions for Setting the DTC
- The ECM must detect 20 or more gear changes without clutch pedal transitions.
Action Taken When the DTC Sets
- The Service Vehicle Soon (SVS) Lamp will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the disgnostic fails. This information will be stored in Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The SVS lamp will turn off after current driving cycle in which the disgnostic runs without a fault.
- A history DTC will clear after 20 consecutive warm-up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 secponds.
DTC P0833 - Clutch Pedal Switch 2 Circuit
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Install a scan tool.
- Turn ON the ignition, with the engine OFF.
- Use the scan tool to monitor the clutch pedal position switch parameter.
- Apply and release the clutch pedal several times.
Does the scan tool indicate a change in state when the clutch pedal is either applied or released? | - | - | Go to Step 3 |
| 3 | Inspect the clutch pedal position switch and the connector. Does the clutch switch or the connector require service? | - | Go to Step 11 | Go to Step 11 |
| 4 | Inspect the clutch pedal position switch fuse for an open. Is the clutch switch fuse open? | - | Go to Step 9 | Go to Step 5 |
| 5 | Using a DMM, measure voltage at the clutch pedal position switch fuse. Does the DMM indicate the specified value? | 12 V | Go to Step 6 | Go to Step 12 |
| 6 | - Turn OFF the ignition.
- Disconnect the clutch pedal position switch connector.
- Turn ON the ignition, with the engine OFF.
- Using a DMM, measure the voltage at the ignition 1 voltage circuit at the switch connector.
Does the DMM indicate the specified value? | B+ | Go to Step 7 | Go to Step 13 |
| 7 | - Clear all DTCs.
- Use the scan tool to monitor the clutch pedal position switch parameter.
- Use a fused jumper wire to repeatedly connect and disconnect terminal 1 and 2 of the clutch pedal position switch electrical connector.
Does the scan tool display that the clutch is applying and releasing? | - | Go to Step 15 | Go to Step 8 |
| 8 | - Turn the ignition switch OFF.
- Disconnect 72 at the ECM.
- Using the DMM, test for continuity and a short to voltage on the clutch pedal position switch signal circuit.
Did you find a short to voltage, high resistance or an open on the clutch pedal position switch signal circuit? | - | Go to Step 14 | Go to Step 16 |
| 9 | - Turn the ignition switch OFF.
- Remove the clutch pedal position switch fuse.
- Disconnect the clutch pedal position switch connector and 72 at the ECM.
- Using a DMM, test for a short to ground on the ignition 1 voltage circuit at the switch connector.
Is the ignition 1 voltage circuit grounded? | - | Go to Step 13 | Go to Step 10 |
| 10 | Using a DMM, test for a short to ground on the clutch pedal position switch signal circuit at the switch connector. Is the clutch pedal position switch signal circuit grounded? | - | Go to Step 14 | Go to Step 15 |
| 11 | Replace the clutch pedal position switch, or repair the connector, as necessary. Did you complete the repair? | - | Go to Step 17 | - |
| 12 | Repair the power distribution circuit to the clutch pedal position switch fuse. Did you complete the repair? | - | Go to Step 17 | - |
| 13 | Repair the open, high resistance, or short to ground in the ignition 1 voltage circuit or a parallel circuit that uses the brake fuse. Did you complete the repair? | - | Go to Step 17 | - |
| 14 | Repair the open, high resistance, short to ground, or short to voltage in the clutch pedal position switch signal circuit. Did you complete the repair? | - | Go to Step 17 | - |
| 15 | Replace the clutch pedal position switch. Is the action complete? | - | Go to Step 17 | - |
| 16 | Replace the ECM. Is the action complete? | - | Go to Step 17 | - |
| 17 | - 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 18 | Go to Step 2 |
| 18 | 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
Park / Neutral Position (PNP) Switch Circuit
Circuit Description
The park / neutral (P/N) switch is a part of the automatic transmission gear selector position switch assembly. The P/N switch is a normally open switch that closes when the transmission is shifted to Park or Neutral position. The ECM applies reference 12 V to the signal circuit of the P/N switch when it is open. When the transmission is shifted to the Park or Neutral position, the P/N switch closes and pulls the P/N switch signal circuit to ground.
Conditions for Setting the DTC
- The signal mismatch between hardware pin and can message.
Action Taken When the DTC Sets
- The Service Vehicle Soon (SVS) Lamp will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the disgnostic fails. This information will be stored in Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The SVS lamp will turn off after current driving cycle in which the disgnostic runs without a fault.
- A history DTC will clear after 20 consecutive warm-up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 secponds.
DTC P0850 - Park / Neutral Position (PNP) Switch Circuit
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Switch on the ignition.
- Using the scan tool, observe the status of the automatic transmission gear position.
- Shift the transmission lever across all gear levels.
Does you find a P/N when the transmission is in park or neutral and In Gear when the transmission lever is in other positions? | - | Go to Step 3 | Go to Step 4 |
| 3 | - Switch off the ignition for 30 seconds.
- Switch on the ignition.
- Shift the transmission lever across all gear levels.
Does DTC P0850 fail this ignition cycle? | - | Go to Step 4 | - |
| 4 | - Remove the transmission position switch wiring connector.
- Connect a test lamp between the ground circuit of the transmission switch and a 12 V.
Does the test lamp illuminate? | - | Go to Step 5 | Go to Step 6 |
| 5 | - Connect a 3 A jumper wire between the signal circuit of the park/neutral signal circuit and a good ground.
- Using the scan tool, observe the status of the transmission gear.
Does you find a change from In Gear to P/N when the jumper wire is connected? | - | Go to Step 8 | Go to Step 7 |
| 6 | Repair the high resistance or open circuit fault condition in the ground circuit of the transmission position switch. Was the repair completed? | - | Go to Step 10 | - |
| 7 | Test the signal circuit of the park / neutral switch for a high resistance, open circuit, short to ground or short to voltage fault condition. Was any fault found and rectified? | - | Go to Step 10 | Go to Step 9 |
| 8 | Replace the transmission position switch. Was the repair completed? | - | Go to Step 10 | - |
| 9 | Replace the ECM. Was the repair completed? | - | Go to Step 10 | - |
| 10 | - Clear the DTCs with a scan tool.
- Switch off the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the conditions for running the DTC.
Does the DTC run and pass? | - | Go to Step 11 | Go to Step 2 |
| 11 | 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) P1138
HO2S Circuit High Voltage During Decel Fuel Cut-Off (DFCO) Sensor 2
Circuit Description
The heated oxygen sensor (HO2S) produces a voltage that varies between 100-900 mV under normal operating conditions. The engine control module (ECM) produces a bias voltage on the HO2S signal circuit of 420-480 mV. The reference ground for the sensor is provided through the ECM. The ECM monitors the signal voltage to determine if the exhaust is lean or rich. The oxygen sensor voltage is high when the exhaust is rich, and low when the exhaust is lean. The ECM constantly monitors the HO2S signal during the Closed Loop operation. If the ECM detects an HO2S voltage that stays above a specified value during a fuel cutoff condition, the DTC will set.
Conditions for Running the DTC
- Time after fuel cut - off is greater than 5 seconds.
- Integrated airmass after fuel cut - off is greater than 15 g.
- Time after dew point end detected is greater than 30 seconds.
Conditions for Setting the DTC
- HO2S filtered voltage is greater than 0.15 V.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
DTC P1138 - HO2S Circuit High Voltage During Decel Fuel Cut-Off (DFCO) Sensor 2
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Allow the engine to reach normal operating temperature.
- Quickly cycle the throttle from closed throttle to wide open throttle (WOT), 3 times within 5 seconds while observing the HO2S Sensor 2 parameter with a scan tool.
Does the voltage react immediately when performing the above action? | - | Go to Step 4 | Go to Step 3 |
| 3 | - Observe the Freeze Frame/Failure Records for this DTC.
- 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 4 | |
| 4 | - Turn OFF the ignition.
- Disconnect the HO2S 2.
- Turn ON the ignition, with the engine OFF.
- Measure the voltage from the HO2S high signal circuit, on the engine harness, side to a good ground with a DMM.
Did the DTC fail this ignition? | 475mV | Go to Step 7 | Go to Step 5 |
| 5 | - Connect a 3-amp fused jumper wire between the HO2S high signal circuit, on the engine harness side connector, and a good ground.
- Observe the HO2S parameter with a scan tool.
Is the voltage less than the specified value? | 25mV | Go to Step 6 | Go to Step 8 |
| 6 | - Remove the jumper wire from the previous step.
- Connect a 3-amp fused jumper wire between the HO2S high signal circuit and the HO2S low signal circuit, on the engine harness side connector.
- Observe the HO2S parameter with a scan tool.
Is the voltage less then the specified value? | - | Go to Step 12 | Go to Step 9 |
| 7 | Measure the voltage from the HO2S low signal circuit, on the engine harness side connector, to a good ground with a DMM. Is the voltage more than the specified value? | 50mV | Go to Step 10 | Go to Step 11 |
| 8 | Test the HO2S high signal circuit for an open or high resistance. Did you find and correct the condition? | - | Go to Step 17 | Go to Step 14 |
| 9 | Test the HO2S low signal circuit for an open or high resistance. Did you find and correct the condition? | - | Go to Step 17 | Go to Step 14 |
| 10 | Test the HO2S low signal circuit for a short to voltage. Did you find and correct the condition? | - | Go to Step 17 | Go to Step 14 |
| 11 | Test the HO2S high signal circuit for a short to voltage or a short to the heater low control circuit. Did you find and correct the condition? | - | Go to Step 17 | Go to Step 14 |
| 12 | The HO2S is detecting a rich exhaust condition or may be contaminated. Inspect for one of the following conditions: - HO2S connector water intrusion
- A silicon-contaminated HO2S
- Fuel-contaminated engine oil
- Incorrect fuel pressure
- Rich fuel injectors
Repair any of the above or similar engine conditions, as necessary. Did you find and correct the condition? | - | Go to Step 17 | Go to Step 13 |
| 13 | Test for shorted terminals and poor connections at the HO2S. Did you find and correct the condition? | - | Go to Step 17 | Go to Step 15 |
| 14 | Test for shorted terminals and poor connections at the engine control module (ECM). Did you find and correct the condition? | - | Go to Step 17 | Go to Step 16 |
| 15 | Replace the affected HO2S. Did you complete the replacement? | - | Go to Step 17 | - |
| 16 | Replace the ECM. Did you complete the replacement? | - | Go to Step 17 | - |
| 17 | - 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 18 |
| 18 | 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) P1551
Throttle Control Lower Position Not Reached During Learn
Circuit Description
The ECM monitors and evaluates the accelerator pedal position (APP) sensors signal voltage along with other sensor inputs to determine the desired throttle opening. To control the throttle plate movement, the ECM applies a pulse width modulated (PWM) signal voltage to the throttle actuator motor through the throttle actuator motor control circuits. In addition, the ECM monitors the signal voltage applied to the throttle actuator motor control circuit. A TAC motor control circuit DTC sets if the ECM detects a fault condition in the TAC circuits or motor performance.
Conditions for Running the DTC
- Under throttle control actuator initialization.
Conditions for Setting the DTC
- The ECM detects that its internal TAC motor output driver does not deactivate when commanded off.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
DTC P1551 - Throttle Control Lower Position Not Reached During Learn
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Switch off the ignition for 30 seconds.
- Operate the vehicle within the conditions for running the DTC.
- Start the engine.
- Quickly depress the accelerator pedal to wide-open throttle then release pedal. Repeat this procedure several times.
- Using the Scan Tool, select the DTC display function.
Did the DTC P1551 fail this ignition? | - | Go to Step 3 | - |
| 3 | Is DTC P0121, P0122, P0123, P0221, P0222 or P0223 also set? | - | Go to applicable DTC table | - |
| 4 | - Disconnect the throttle actuator wiring connector.
- Inspect the throttle plate for the following:
- excessive dirt build-up in the throttle body,
- not in rest position,
- binding open or binding close,
- binding when moving from open to close or close to open position, and
- free to move open or close without spring pressure.
Did you find and correct the condition? | - | Go to Step 13 | Go to Step 5 |
| 5 | Inspect the engine for fault conditions that causes incorrect idle speed. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 6 |
| 6 | - Switch on the ignition with the engine not running.
- Using a digital multimeter, measure the voltage between the TAC positive circuit and the ECM housing.
Is the voltage within the specified range? | 2 - 4 V | Go to Step 7 | Go to Step 9 |
| 7 | - Switch on the ignition with the engine not running.
- Using a digital multimeter, measure the voltage between the TAC positive control circuit and the ECM housing.
Is the voltage within the specified range? | 2 - 4 V | Go to Step 8 | Go to Step 9 |
| 8 | - Switch off the ignition.
- Connect a test lamp between the positive and negative control circuit of the TAC.
- Switch on the ignition for about 5 seconds then switch off while observing the test lamp.
Does the test lamp illuminate briefly each time the ignition cycles? | - | Go to Step 11 | Go to Step 10 |
| 9 | Test the TAC control circuit that measured outside the specified value for a high resistance, open circuit, short to ground or short to voltage fault condition. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 12 |
| 10 | Test the positive and negative control circuits of the TAC for a shorted together fault condition. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 12 |
| 11 | Replace the throttle body assembly. Did you complete the replacement? | - | Go to Step 13 | - |
| 12 | Replace the ECM. Did you complete the replacement? | - | Go to Step 13 | - |
| 13 | - 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 14 |
| 14 | 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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