DTC P0123 [LF, L3]

id0102a3804300

DTC P0123

TP sensor circuit high input

DETECTION CONDITION

• If the PCM detects the TP sensor voltage at PCM terminal 2I is above 4.9 V while the engine is running, the PCM determines that the TP circuit has 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 A and PCM terminal 2AA
• Short to constant voltage supply circuit in wiring harness between TP sensor terminal B and PCM terminal 2I

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related service 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 TP SENSOR CONNECTOR
• Turn the ignition switch off.
• Verify that the TP sensor connector is connected securely.
• Is connector normal?
Yes
Go to the next step.
No
Connect the connector securely, then go to Step 11.
4
INSPECT POOR CONNECTION OF TP SENSOR CONNECTOR
• Disconnect the TP sensor 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 11.
No
Go to the next step.
5
INSPECT TP SENSOR
• Perform TP sensor inspection.
• Is TP sensor normal?
Yes
Go to the next step.
No
Replace the TP sensor, then go to Step 11.
6
INSPECT TP SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
• Turn the ignition switch to the ON position (Engine off).
• Measure the voltage between terminal B and body ground.
• Is the voltage above 4.9 V?
Yes
Repair or replace short to power supply. Then, go to Step 11.
No
Go to the next step.
7
VERIFY TP SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Turn the ignition switch off.
• Inspect for continuity between TP sensor terminal B (wiring harness-side) and PCM terminal 2I.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
8
VERIFY TP SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between TP sensor terminal A and body ground.
• Is there continuity?
Yes
Repair or replace open circuit in wiring harness between TP sensor terminal A (wiring harness-side) and PCM terminal 2AA (wiring harness-side). Then, go to Step 11.
No
Go to the next step.
9
INSPECT PCM CONNECTOR
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair terminal, then go to Step 11.
No
Go to Step 11.
10
VERIFY TP SIGNAL CIRCUIT FOR SHORT TO CONSTANT VOLTAGE CIRCUIT
• Inspect the continuity between TP sensor terminals B and C.
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Go to the next step.
11
VERIFY TROUBLESHOOTING OF DTC P0123 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
• Are any DTC present?
Yes
Go to the applicable DTC troubleshooting.
No
Troubleshooting completed.