Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Mazda >> 2006 >> 3 i, 2.0 G, Standard >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] - (5 Of 5) >> DTC P2123

DTC P2123

DETECTION CONDITION AND POSSIBLE CAUSE (DTC P2123 - LF, L3)

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 in the first drive cycle.
  • 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 
  • APP sensor No. 1 malfunction
  • Connector or terminal malfunction
  • Short to power supply in wiring harness between APP sensor terminal B and PCM terminal 1AP(1), (3), 1Y(2)
  • Open circuit in wiring harness between APP sensor terminal C and PCM terminal 1AS(1), 1AA(2), 1AV(3)
  • PCM malfunction
G04313427Courtesy of MAZDA MOTORS CORP.
(1) California emission regulation applicable model
(2) Except for California emission regulation applicable model with LF ATX
(3) Except for California emission regulation applicable model with LF MTX, L3
DIAGNOSTIC PROCEDURE CHART

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 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 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 (wiring harness-side) 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  Yes Replace the APP sensor, then go to Step 8. (See ACCELERATOR PEDAL REMOVAL/INSTALLATION ).
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 (wiring harness-side) and PCM terminal 1AS(1), 1AA(2), 1AV(3) (wiring harness-side).
  • 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 WDS or equivalent.
  • Start the engine.
  • Is the same DTC present?
Yes Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection. (See DTC TABLE ).
No DTC troubleshooting completed.
(1) California emission regulation applicable model
(2) Except for California emission regulation applicable model with LF ATX
(3) Except for California emission regulation applicable model with LF MTX, L3