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Home >> Mazda >> 2021 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (5 Of 6) >> DTC P2127-00: App Sensor No. 2 Circuit Low Input >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2127:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
- 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 CONDITION
  • Switch the ignition 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 connector and/or terminals, then go to Step 9.
No Go to the next step.
4 INSPECT APP SENSOR No. 2 CIRCUIT FOR SHORT TO GROUND
  • Verify that the APP sensor connector is disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • APP sensor terminal F
    • APP sensor terminal E
  • Is there continuity?
Yes Disconnect the PCM connector and inspect the wiring harness for short to ground.
  • If the short to ground circuit could be detected in the wiring harness:
    • Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
      • APP sensor terminal F-PCM terminal 2AC
      • APP sensor terminal E-PCM terminal 2AR

    If there is a common connector:

  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
  • Repair or replace the malfunctioning part.

    If there is no common connector:

  • Repair or replace the wiring harness which has a short to ground.
  • If the short to ground circuit could not be detected in the wiring harness:

Go to Step 9.
No Go to the next step.
5 INSPECT PCM CONNECTOR CONDITION
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
Yes Repair or replace the connector and/or terminals, then go to Step 9.
No Go to the next step.
6 INSPECT APP SENSOR No. 2 SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER
  • Verify that the APP sensor and PCM connectors are disconnected.
  • Inspect for continuity between APP sensor terminals E and D (wiring harness-side).
  • Is there continuity?
Yes Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • APP sensor terminal E-PCM terminal 2AR
  • APP sensor terminal D-PCM terminal 2AT

    If there is a common connector:

  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to each other.
  • Repair or replace the malfunctioning part. If there is no common connector:
  • Repair or replace the wiring harness which has a short to each other.

Go to Step 9.
No Go to the next step.
7 INSPECT APP SENSOR No. 2 CIRCUIT FOR OPEN CIRCUIT
  • Verify that the APP sensor and PCM connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side):
    • APP sensor terminal F-PCM terminal 2AC
    • APP sensor terminal E-PCM terminal 2AR
  • Is there continuity?
Yes Go to the next step.
No Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • APP sensor terminal F-PCM terminal 2AC
  • APP sensor terminal E-PCM terminal 2AR If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part. If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

Go to Step 9.
8 INSPECT APP SENSOR No. 2
Yes Replace the accelerator pedal, then go to the next step.
(See ACCELERATOR PEDAL REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
9 VERIFY DTC TROUBLESHOOTING COMPLETED
Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE
Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No DTC troubleshooting completed.