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Diagnostic procedure

DTC P0123 [L3] DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has FREEZE FRAME DATA (Mode 12) been recorded?
Yes Go to the next step.
No Record FREEZE FRAME DATA (Mode 12) on 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 available repair information.
  • If vehicle is not repaired, go to the next step.
No Go to next step.
3 INSPECT THROTTLE BODY CONNECTOR 
  • Turn the ignition switch off.
  • Verify that the throttle body connector is connected securely.
  • Is the connector normal?
Yes Go to the next step.
No Connect the connector securely, then go to Step 10.
4 INSPECT THROTTLE BODY CONNECTION FOR POOR CONNECTION 
  • Disconnect the throttle body connector.
  • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion).
  • Is there any malfunction?
Yes Repair or replace the terminal, then go to Step 10.
No Go to the next step.
5 INSPECT TP SENSOR 
Yes Go to the next step.
No Replace the throttle body, then go to Step 10.
6 INSPECT TP1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between throttle body terminal A (wiring-harness-side)and body ground.
  • Is the voltage above 4.85 V? 
Yes Repair or replace short to power supply. Then, go to Step 10.
No Go to the next step.
7 VERIFY TP SIGNAL CIRCUIT FOR SHORT TO CONSTANT VOLTAGE CIRCUIT 
  • Inspect for continuity between throttle body terminals A and B (wiring-harness-side).
  • Is there continuity?
Yes Repair or replace suspected harness, then go to Step 10.
No Go to the next step.
8 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion).
  • Is there any malfunction?
Yes Repair the terminal, then go to Step 10.
No Go to the next step.
9 VERIFY TP SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between throttle body connector terminal D (wiring-harness-side) and PCM connector terminal 2AP (wiring-harness-side).
  • Is there continuity?
Yes Go to the next step.
No Repair or replace the wiring harness for open circuit, then go to the next step.
10 VERIFY TROUBLESHOOTING OF DTC P0123 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/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.
11 VERIFY AFTER REPAIR PROCEDURE 
Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No Troubleshooting completed.