[Previous][Next]
DTC P2138: Accelerator Pedal Position Sensor (main and sub) Range/Performance Problem
 
 
 
 
ACCELERATOR PEDAL POSITION SENSOR (main and sub) RANGE/PERFORMANCE PROBLEM CIRCUIT
  • Refer to DTC P2122 - Accelerator Pedal Position Sensor (main) Circuit Low Input .
  • Refer to DTC P2127 - Accelerator Pedal Position Sensor (sub) Circuit Low Input .
 
 
CIRCUIT OPERATION
  • Refer to DTC P2122 - Accelerator Pedal Position Sensor (main) Circuit Low Input .
  • Refer to DTC P2127 - Accelerator Pedal Position Sensor (sub) Circuit Low Input .
 
 
TECHNICAL DESCRIPTION
  • ECM checks the accelerator pedal position sensor output signal characteristics for abnormal conditions.
 
 
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 <Range/Performance problem -relation between main and sub>
Logic Flow Chart
 
 
Check Condition
  • Ignition switch is "ON" position.
Judgment Criterion
  • The accelerator pedal position sensor (main) output voltage subtracted from the accelerator pedal position sensor (sub) output voltage is more than 0.4 volt for 0.4 second.
    noteThe accelerator pedal position sensor voltage used for the judgment is converted into the accelerator pedal position sensor voltage for the internal processing by the ECM.
 
 
DTC SET CONDITIONS <Range/Performance problem -relation between main and sub>
Logic Flow Chart
 
 
Check Condition
  • Ignition switch is "ON" position.
Judgment Criterion
  • The accelerator pedal position sensor (sub) output voltage subtracted from the accelerator pedal position sensor (main) output voltage is more than 0.4 volt for 0.4 second.
    noteThe accelerator pedal position sensor voltage used for the judgment is converted into the accelerator pedal position sensor voltage for the internal processing by the ECM.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • Throttle opening degree is restricted.
  • Throttle opening degree position is in default position if accelerator pedal position sensor (sub) fails.
 
 
OBD-II DRIVE CYCLE PATTERN
  • None.
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be stored are:)
  • Accelerator pedal position sensor failed.
  • Harness damage in accelerator pedal position sensor circuit or connector damage.
  • ECM failed.

 
 
DIAGNOSIS
Required Special Tools:
  • MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
  • MB992745: V.C.I.-Lite main harness A
  • MB992747: V.C.I.-Lite USB cable short
  • MB992748: V.C.I.-Lite USB cable long
  • MB991958: Scan Tool (M.U.T.-III Sub Assembly)
    • MB991824: Vehicles Communication Interface (V.C.I.)
    • MB991827: M.U.T.-III USB Cable
    • MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Using scan tool (M.U.T.-III), check data list item 11: Accelerator Pedal Position Sensor (main).
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
(1) Connect scan tool (M.U.T-III). Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) .
(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool (M.U.T.-III) 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.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is the sensor operating properly?
Go to Step 2.
Refer to, DTC P2122 - Accelerator Pedal Position Sensor (main) Circuit Low Input , DTC P2123 - Accelerator Pedal Position Sensor (main) Circuit High Input .
 
STEP 2. Using scan tool (M.U.T.-III), check data list item 12: Accelerator Pedal Position Sensor (sub).
(1) Turn the ignition switch to the "ON" position.
(2) Set scan tool (M.U.T.-III) 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.
Is the sensor operating properly?
Go to Step 3.
Refer to, DTC P2127 - Accelerator Pedal Position Sensor (sub) Circuit Low Input , DTC P2128 - Accelerator Pedal Position Sensor (sub) Circuit High Input .
 
STEP 3. Check the continuity at accelerator pedal position sensor harness side connector.
(1) Disconnect the accelerator pedal position sensor connector and measure at the harness side.
(2) Check for the continuity between terminal APSE line and ground.
  • Continuity (2 ohms or less)
Does continuity exist?
Go to Step 5.
Go to Step 4.
 
STEP 4. Check of harness damage in APSE line between accelerator pedal position sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 10.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 5. Check the continuity at accelerator pedal position sensor harness side connector.
(1) Disconnect the accelerator pedal position sensor connector and measure at the harness side.
(2) Check for the continuity between terminal APE line and ground.
  • Continuity (2 ohms or less)
Does continuity exist?
Go to Step 8.
Go to Step 6.
 
STEP 6. Check of harness damage in APE line between accelerator pedal position sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 7.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 7. Using scan tool (M.U.T.-III), 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.
Is DTC P2138 stored?
Replace the ECM (Refer to, Removal and Installation ). Then go to Step 13.
It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions .
 
STEP 8. Check of harness damage in APS5 line between accelerator pedal position sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 9.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 9. Check of harness damage in AP5 line between accelerator pedal position sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 10.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 10. Check of harness damage in APSM line between accelerator pedal position sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 11.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 11. Check of harness damage in APSS line between accelerator pedal position sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 12.
Repair the connector(s) or wiring harness. Then go to Step 13.
 
STEP 12. Replace the accelerator pedal assembly.
(1) Replace the accelerator pedal assembly.
(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.
Is DTC P2138 stored?
Replace the ECM (Refer to, Removal and Installation ). Then go to Step 13.
The inspection is complete.
 
STEP 13. Using scan tool (M.U.T.-III), 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.
Is DTC P2138 stored?
Retry the troubleshooting.
The inspection is complete.