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DTC P2123

DTC P2123 APP sensor NO. 1 circuit high input
DETECTION CONDITION 
  • The PCM monitors the input voltage from the APP sensor NO. 1 when the engine is running. If the input voltage is more than 4.8 V  , the PCM determines that the APP sensor NO. 1 circuit input voltage is high.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • APP sensor connector or terminals malfunction
  • PCM connector or terminals malfunction
  • Short to power supply in wiring harness between APP sensor terminal F and PCM terminal 1AO
  • Open circuit in wiring harness between APP sensor terminal E and PCM terminal 1 AS
  • APP sensor NO. 1 malfunction
  • PCM malfunction
G07878152
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA (Mode 12) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 INSPECT APP SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the APP sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 8.
No Go to the next step.
4 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 8.
No Go to the next step.
5 INSPECT APP SENSOR NO. 1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • APP sensor and PCM connectors are disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between APP sensor terminal F (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 8.
No Go to the next step.
6 INSPECT APP SENSOR NO. 1 GROUND CIRCUIT FOR OPEN CIRCUIT 
  • APP sensor and PCM connectors are disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between APP sensor terminal E (wiring harness-side) and PCM terminal 1AS (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 8.
7 INSPECT APP SENSOR NO. 1 
 Yes Replace the accelerator pedal, then go to the next step.
(See ACCELERATOR PEDAL REMOVAL/INSTALLATION ).
No Go to the next step.
8 VERIFY TROUBLESHOOTING OF DTC P2123 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOEO or KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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