DTC P0123 [L8, LF]

id0102b1804300

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

POSSIBLE CAUSE

• TP sensor No.1 malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between throttle body terminal C and PCM terminal 2AP
• Open circuit in wiring harness between throttle body terminal F and PCM terminal 2AK
• Short to constant voltage supply circuit in wiring harness between throttle body terminal F and PCM terminal 2AK
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Have 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 SERVICE 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 NO.1
• Inspect the TP sensor No.1.
• Is the TP sensor No.1 okay?
Yes
Go to the next step.
No
Replace the throttle body, then go to Step 9.
5
INSPECT TP SENSOR NO.1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
• 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 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 SENSOR NO.1 SIGNAL CIRCUIT FOR SHORT TO CONSTANT VOLTAGE CIRCUIT
• Inspect for continuity between throttle body terminals E and F (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 NO.1 GROUND CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between throttle body terminal C (wiring harness-side) and PCM terminal 2AP (wiring harness-side).
• Is there continuity?
Yes
Repair or replace for an open circuit between TP sensor No.1 terminal C (wiring harness-side) and PCM 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 M-MDS.
• 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.