DTC P2123[LF ATX (FN4A-EL), L3 ATX]

id0102b6811800

DTC P2123

Accelerator pedal position (APP) sensor No.1 circuit high input
DETECTION CONDITION
•  The PCM monitors the input voltage from APP sensor No.1 when the engine is running. If the input voltage is above 4.8 V, the PCM determines that the APP sensor No.1 circuit input voltage is high.
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.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  APP sensor No.1 malfunction
•  Connector or terminal malfunction
•  Short to power supply in wiring harness between APP sensor terminal B and PCM terminal 1Y
•  Open circuit in wiring harness between APP sensor terminal C and PCM terminal 1AA
•  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.
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 APP SENSOR CONNECTOR FOR POOR CONNECTION
•  Turn the ignition switch off.
•  Disconnect the APP 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 8.
No
Go to the next step.
4
INSPECT APP SENSOR NO.1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Turn the ignition switch to the ON position (Engine off).
•  Measure the voltage between APP sensor terminal B and body ground.
•  Is the voltage B+?
Yes
Repair or replace the wiring harness for a possible short to power supply, then go to Step 8.
No
Go to the next step.
5
INSPECT APP SENSOR NO.1
•  Inspect APP sensor No.1.
•  Is there any malfunction?
Yes
Replace the APP sensor, then go to Step 8.
(See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION[LF, L3].)
No
Go to the next step.
6
INSPECT PCM CONNECTOR FOR POOR CONNECTION
•  Turn the ignition switch off.
•  Disconnect the PCM 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 8.
No
Go to the next step.
7
INSPECT APP SENSOR NO.1 GROUND CIRCUIT FOR OPEN CIRCUIT
•  Turn the ignition switch off.
•  Inspect for continuity between APP sensor terminal C and PCM terminal 1AA.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to the next step.
8
VERIFY TROUBLESHOOTING OF DTC P2123 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Start the engine.
•  Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION[LF, L3].)
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Is any DTC present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[LF ATX (FN4A-EL), L3 ATX].)
No
DTC troubleshooting completed.