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 DTC P0123 [L8, LF, L3]

DTC P0123 [L8, LF, L3]

id0102a1804300

DTC P0123

TP sensor No.1 circuit high input

DETECTION CONDITION

• If the PCM detects the TP sensor No.1 voltage is to be above 4.85 V after ignition switch to the ON position, PCM determines that TP circuit has a malfunction.
Diagnostic support note
• This is a continuous monitor (CCM).
• MIL illuminates if the PCM detects the above malfunction condition in first drive cycles.
• PENDING CODE is available if the PCM detects the above malfunction condition.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• TP sensor malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between TP sensor terminal D and PCM terminal 2AP
• Open circuit in wiring harness between TP sensor terminal A and PCM terminal 2AK
• Short to constant voltage supply circuit in wiring harness between TP sensor terminal A and PCM terminal 2AK
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT THROTTLE BODY CONNECTION FOR POOR CONNECTION
• 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 terminal, then go to Step 9.
No
Go to the next step.
4
INSPECT TP SENSOR
• Inspect the TP sensor.
• Is the TP sensor okay?
Yes
Go to the next step.
No
Replace the throttle body, then go to Step 9.
5
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 4.9 V?
Yes
Repair or replace for a short to power supply. Then, go to Step 9.
No
Go to the next step.
6
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 wiring harness, then go to Step 9.
No
Go to the next step.
7
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair the terminal, then go to Step 9.
No
Go to the next step.
8
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
Repair or replace for an open circuit between TP sensor connector terminal D (wiring harness-side) and PCM connector terminal 2AP (wiring harness-side). Then, go to the step.
No
Go to the next step.
9
VERIFY TROUBLESHOOTING OF DTC P0123 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Turn the ignition switch to the ON position (Engine off).
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine and warm it up completely.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
• Is any DTC present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.