P2138
DTC P2138: Accelerator Pedal Position Sensor (main and sub) Circuit Range/Performance ProblemAccelerator Pedal Position Sensor (main) Circuit:
Accelerator Pedal Position Sensor (sub) Circuit:
CAUTION: If DTC P2138 has been set, TCL related DTC U1120 and U1400 are also set. After P2138 has been diagnosed, don't forget to erase DTC U1120 and U1400.
CIRCUIT OPERATION
- A 5-volt power supply is applied on the accelerator pedal position sensor (main) power terminal (terminal No. 1) from the ECM
The ground terminal (terminal No. 2) is grounded with ECM
- A 5-volt power supply is applied on the accelerator pedal position sensor (sub) power terminal (terminal No. 4) from the ECM
The ground terminal (terminal No. 5) is grounded with ECM
TECHNICAL DESCRIPTION
- ECM
DESCRIPTIONS OF MONITOR METHODS
Detect malfunction if the relation between accelerator pedal position sensor (main) and accelerator pedal position sensor (sub) is wrong.
MONITOR EXECUTION
Continuous
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Not applicable
Sensor (The sensor below is determined to be normal)
- Not applicable
DTC SET CONDITIONS
Logic Flow Chart:
Logic Flow Chart:
Logic Flow Chart
Check Conditions
- Ignition switch is "ON" position.
- Accelerator pedal position sensor (main) output voltage is between 0.6 and 4.8 volts.
- Accelerator pedal position sensor (sub) output voltage is between 0.2 and 4.8 volts.
- Change of accelerator pedal position sensor (sub) output voltage per 25 milliseconds is lower than 0.06 volt.
Judgement Criteria
- Voltage obtained with the formula given below is 1.0 volt or higher for 1 second: [accelerator pedal position sensor (sub) output voltage +0.3 volt] - accelerator pedal position sensor (main) output voltage.
or
- Voltage obtained with the formula given below is 1.0 volt or higher for 0.2 second: [accelerator pedal position sensor (main) output voltage - [accelerator pedal position sensor (sub) output voltage +0.3 volt].
OBD-II DRIVE CYCLE PATTERN
None.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are)
- Accelerator pedal position sensor failed.
- Harness damage in accelerator pedal position sensor circuit or connector damage.
- ECM failed.
- PCM failed.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
STEP 1. Check harness connector C-22 at accelerator pedal position sensor for damage.
Q: Is the harness connector in good condition?
YES: Go to Step 2.
NO: Repair or replace it. Then go to Step 16.
STEP 2. Check the continuity at accelerator pedal position sensor harness side connector C-22.
1. Disconnect the connector C-22 and measure at the harness side.
2. Measure the continuity between terminal No. 2 and ground.
- Should be less than 2 Ohms.
Q: Does continuity exist?
YES: Go to Step 6.
NO: Go to Step 3.
STEP 3. Check harness connector B-19 at ECM
Q: Is the harness connector in good condition?
YES: Go to Step 4.
NO: Repair or replace it. Then go to Step 16.
STEP 4. Check for harness damage between accelerator pedal position sensor connector C-22 (terminal No. 2) and ECM
Q: Is the harness wire in good condition?
YES: Go to Step 5.
NO: Repair it. Then go to Step 16.
STEP 5. Using scan tool MB991958, read the diagnostic trouble code (DTC).
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. After the DTC has been deleted, read the DTC again.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P2138 set?
YES: Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Refer to Encrypted Code Registration Criteria Table. Then go to Step 16.
NO: It can be assumed that this malfunction is intermittent.
STEP 6. Check the continuity at accelerator pedal position sensor harness side connector C-22.
1. Disconnect the connector C-22 and measure at the harness side.
2. Measure the continuity between terminal No. 5 and ground.
- Should be less than 2 Ohms.
Q: Does continuity exist?
YES: Go to Step 10.
NO: Go to Step 7.
STEP 7. Check harness connector B-19 at ECM
Q: Is the harness connector in good condition?
YES: Go to Step 8.
NO: Repair or replace it. Then go to Step 16.
STEP 8. Check for harness damage between accelerator pedal position sensor connector C-22 (terminal No. 5) and ECM
Q: Is the harness wire in good condition?
YES: Go to Step 9.
NO: Repair it. Then go to Step 16.
STEP 9. Using scan tool MB991958, read the diagnostic trouble code (DTC).
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. After the DTC has been deleted, read the DTC again.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P2138 set?
YES: Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Refer to Encrypted Code Registration Criteria Table. Then go to Step 16.
NO: It can be assumed that this malfunction is intermittent.
STEP 10. Check harness connector B-19 at ECM
Q: Is the harness connector in good condition?
YES: Go to Step 11.
NO: Repair or replace it. Then go to Step 16.
STEP 11. Check for harness damage between accelerator pedal position sensor connector C-22 (terminal No. 1) and ECM
Q: Is the harness wire in good condition?
YES: Go to Step 12.
NO: Repair it. Then go to Step 16.
STEP 12. Check for harness damage between accelerator pedal position sensor connector C-22 (terminal No. 4) and ECM
Q: Is the harness wire in good condition?
YES: Go to Step 13.
NO: Repair it. Then go to Step 16.
STEP 13. Check for harness damage between accelerator pedal position sensor connector C-22 (terminal No. 3) and ECM
Q: Is the harness wire in good condition?
YES: Go to Step 14.
NO: Repair it. Then go to Step 16.
STEP 14. Check for harness damage between accelerator pedal position sensor connector C-22 (terminal No. 6) and ECM
Q: Is the harness wire in good condition?
YES: Go to Step 15.
NO: Repair it. Then go to Step 16.
STEP 15. Replace the accelerator pedal position sensor.
1. Replace the accelerator pedal position sensor.
2. Turn the ignition switch to the "ON" position.
3. After the DTC has been deleted, read the DTC again.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P2138 set?
YES: Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Refer to Encrypted Code Registration Criteria Table. Then go to Step 16.
NO: The inspection is complete.
STEP 16. Using scan tool MB991958, read the diagnostic trouble code (DTC).
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. After the DTC has been deleted, read the DTC again.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P2138 set?
YES: Retry the troubleshooting.
NO: The inspection is complete.