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Home >> Mazda >> 2007 >> 6 Mazdaspeed >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3 With TC] >> DTC P2123 >> Diagnostic procedure
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Diagnostic procedure

DTC P2123 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA been recorded?
 Yes Go to the next step.
No Record FREEZE FRAME DATA on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Check for related Service Bulletins and/or online repair information availability.
  • Is any related repair information available?
 Yes Perform the 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 
  • Turn the ignition switch to off.
  • Verify that the APP sensor connector is connected securely.
  • Is the connector normal?
 Yes Go to the next step.
No Connect the connector securely, then go to Step 10.
4 INSPECT APP SENSOR CONNECTOR FOR POOR CONNECTION 
  • 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 suspected terminal, then go to Step 10.
No Go to the next step.
5 INSPECT APP SENSOR 
 Yes Go to the next step.
No Replace the APP sensor, then go to Step 10.
6 INSPECT APP1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Turn ignition switch to the ON position (Engine off).
  • Measure the voltage between APP sensor terminal F (harness-side) and body ground.
  • Is the voltage above 4.8 V? 
 Yes Repair or replace a short to power supply. Then, go to Step 10.
No Go to the next step.
7 VERIFY APP SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT 
  • Disconnect the PCM connector.
  • Inspect for continuity between APP sensor terminal E (harness side) and PCM terminal 3A (harness side).
  • Is there continuity?
 Yes Repair or replace for an open circuit between APP sensor terminal F (harness-side) and PCM connector terminal 3D (harness-side). Then, go to Step 10.
No Go to the next step.
8 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair the terminal, then go to Step 10.
No Go to the next step.
9 VERIFY TP SIGNAL CIRCUIT FOR SHORT TO CONSTANT VOLTAGE CIRCUIT 
  • Inspect for continuity between throttle body terminals D and F (harness side).
  • Is there continuity?
 Yes Repair or replace the suspected wiring harness, then go to the next step.
No Go to the next step.
10 VERIFY TROUBLESHOOTING OF DTC P2123 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn ignition switch to the ON position (Engine off).
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • 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 ).
No Go to the next step.
11 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No Troubleshooting completed.
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