P1237
DTC P1237: Accelerator Pedal Position Sensor PlausibilityTECHNICAL DESCRIPTION
Compare the output value of the accelerator pedal position sensor (main) with that of the accelerator pedal position sensor (sub).
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:
Check Conditions
- Change of accelerator pedal position sensor (sub) output voltage per 40 milliseconds is less than 0.06 volt.
- Range/performance error of accelerator pedal position sensor (main and sub) circuit is not detected.
Judgement Criterion
- The difference between the accelerator pedal position sensor (main) output voltage and the accelerator pedal position sensor (sub) output voltage is more than 0.4 volt for 0.5 second.
NOTE: The accelerator pedal position sensor voltage used for the judgement is converted into the accelerator pedal position sensor voltage for the internal processing by the ECM.
FAIL-SAFE AND BACKUP FUNCTION
- Throttle opening degree position is in default position.
OBD-II DRIVE CYCLE PATTERN
- None.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Accelerator pedal position sensor system failed.
- ECM failed.
DIAGNOSIS
Required Special Tool:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
STEP 1. 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. Read the DTC.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the diagnostic trouble code other than P1237 set?
YES : Refer to, Diagnostic Trouble Code Chart. Diagnostic Trouble Code Descriptions
NO : Go to Step 2.
STEP 2. Using scan tool MB991958, check data list item 11: Accelerator Pedal Position Sensor (main).
1. Turn the ignition switch to the "ON" position.
2. Set scan tool MB991958 to the data reading mode for item 11, Accelerator Pedal Position Sensor (main).
- Output voltage should be between 900 and 1,100 millivolts when foot is released from accelerator pedal.
- Output voltage should be 4,000 millivolts or more when accelerator pedal is fully depressed.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?
YES : Go to Step 3.
NO : Refer to, DTC P2122 - Accelerator Pedal Position Sensor (main) Circuit Low Input, P2122 DTC P2123 - Accelerator Pedal Position Sensor (main) Circuit High Input. P2123
STEP 3. Using scan tool MB991958, check data list item 12: Accelerator Pedal Position Sensor (sub).
1. Turn the ignition switch to the "ON" position.
2. Set scan tool MB991958 to the data reading mode for item 12, Accelerator Pedal Position Sensor (sub).
- Output voltage should be between 400 and 600 millivolts when foot is released from accelerator pedal.
- Output voltage should be 2,000 millivolts or more when accelerator pedal is fully depressed.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?
YES : Go to Step 4.
NO : Refer to, DTC P2127 - Accelerator Pedal Position Sensor (sub) Circuit Low Input, P2127 DTC P2128 - Accelerator Pedal Position Sensor (sub) Circuit High Input. P2128
STEP 4. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. After the DTC has been deleted, read the DTC again.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P1237 set?
YES : Replace the ECM. Then go to Step 5.
NO : It can be assumed that this malfunction is intermittent.
STEP 5. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. After the DTC has been deleted, read the DTC again.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P1237 set?
YES : Retry the troubleshooting.
NO : The inspection is complete.