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

STEP

INSPECTION

ACTION

1

• 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 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

• 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 the TP sensor No.1.

  (See THROTTLE POSITION (TP) SENSOR INSPECTION [LF])

• Is the TP sensor No.1 okay?

Yes

Go to the next step.

No

Replace the throttle body, then go to Step 9.

(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF].)

5

• 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

• 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

• 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

• 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

• 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.

(See PCM REMOVAL/INSTALLATION [LF].)

No

Go to the next step.

10

• Perform the “AFTER REPAIR PROCEDURE”.

  (See AFTER REPAIR PROCEDURE [LF].)

• Is any DTC present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [LF].)

No

Troubleshooting completed.