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DTC P0123

DTC P0123 TP sensor NO. 1 circuit high input
DETECTION CONDITION 
  • The PCM monitors the input voltage from the TP sensor NO. 1 when the engine is running. If the input voltage is more than 4.8 V,  the PCM determines that the TP 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 
  • Throttle body connector or terminals malfunction
  • PCM connector or terminals malfunction
  • Short to power supply in wiring harness between throttle body terminal F and PCM terminal 2AK
  • Open circuit in wiring harness between throttle body terminal C and PCM terminal 2P
  • TP sensor NO. 1 malfunction
  • PCM malfunction
G07878107
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 THROTTLE BODY CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the throttle body 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 TP SENSOR NO. 1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Throttle body and PCM connectors are disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between throttle body 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 TP SENSOR NO. 1 GROUND CIRCUIT FOR OPEN CIRCUIT 
  • Throttle body and PCM connectors are disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between throttle body terminal C (wiring harness-side) and PCM terminal 2P (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 TP SENSOR NO. 1 
 Yes Replace the throttle body, then go to the next step.
(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION ).
No Go to the next step.
8 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 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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