DTC P0123[LF ATX (FN4A-EL), L3 ATX]

id0102b6804300

DTC P0123

TP sensor No.1 circuit high input

DETECTION CONDITION

•  If the PCM detects the TP sensor voltage is above 4.85 V while the engine is running, the PCM determines that the TP circuit has malfunction.

Diagnostic support note

•  This is a continuous monitor (CCM).

•  The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.

•  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 2O

•  Short to power supply circuit in wiring harness between TP sensor terminal A and PCM terminal 2M

•  PCM malfunction

DTC P0123	TP sensor No.1 circuit high input
DETECTION CONDITION	• If the PCM detects the TP sensor voltage is above 4.85 V while the engine is running, the PCM determines that the TP circuit has malfunction. Diagnostic support note • This is a continuous monitor (CCM). • The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle. • 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 2O • Short to power supply circuit in wiring harness between TP sensor terminal A and PCM terminal 2M • PCM malfunction

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.
1		No	Record FREEZE FRAME DATA on 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.
2		No	Go to the next step.
3	INSPECT THROTTLE BODY CONNECTOR • Turn the ignition switch off. • Verify that the throttle body connector is connected securely. • Is the connector normal?	Yes	Go to the next step.
3		No	Connect the connector securely, then go to Step 10.
4	INSPECT THROTTLE BODY CONNECTION FOR POOR CONNECTION • Disconnect the throttle body connector. • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion). • Is there any malfunction?	Yes	Repair or replace the terminal, then go to Step 10.
4		No	Go to the next step.
5	INSPECT TP SENSOR • Inspect the TP sensor. (See THROTTLE POSITION (TP) SENSOR INSPECTION[LF, L3]) • Is the TP sensor okay?	Yes	Go to the next step.
5		No	Replace the throttle body, then go to Step 10.
6	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 and body ground. • Is the voltage above 4.85 V?	Yes	Repair or replace short to power supply. Then, go to Step 10.
6		No	Go to the next step.
7	VERIFY TP SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY CIRCUIT • Inspect for continuity between throttle body terminals A and B. • Is there continuity?	Yes	Repair or replace suspected harness, then go to Step 10.
7		No	Go to the next step.
8	INSPECT PCM CONNECTOR FOR POOR CONNECTION • Disconnect the PCM connector. • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion). • Is there any malfunction?	Yes	Repair the terminal, then go to Step 10.
8		No	Go to the next step.
9	VERIFY TP SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect for continuity between throttle body connector terminal D and PCM connector terminal 2O. • Is there continuity?	Yes	Repair or replace open circuit between TP sensor connector terminal A and PCM connector terminal 2O. Then, go to the step.
9		No	Go to the next step.
10	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. (See PCM REMOVAL/INSTALLATION[LF, L3].)
10		No	Go to the next step.
11	VERIFY AFTER REPAIR PROCEDURE • Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE[LF ATX (FN4A-EL), L3 ATX].) • Is any DTC present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE[LF ATX (FN4A-EL), L3 ATX].)
11		No	Troubleshooting completed.