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Home >> Mazda >> 2021 >> 3 Select, 4D Hatchback, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (VINS 7, L, M) (3 Of 4) >> DTC P18A4-00: Pcm I-ACTIV AWD Control System >> Diagnostic Procedure
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Diagnostic Procedure

DTC P18A4:00 (PCM, VINs 7, L, M) DIAGNOSTIC PROCEDURE

Step Inspection Results Action
1 RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION
  • Record the freeze frame data/snapshot data.
    NOTE:
    • Recording can be facilitated using the screen capture function of the PC.
- Go to the next step.
2 VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY
  • Verify related Service Bulletins, on-line repair information, or Service Information availability.
  • Is any related Information available?
Yes Perform repair or diagnosis according to the available information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 ALLOW THE VEHICLE TO COOL DOWN FOR WHILE
  • Switch the ignition to off and allow vehicle to cool down.
- Go to the next step.
4 INSPECT i-ACTIV AWD SYSTEM-RELATED PART CONNECTORS FOR MALFUNCTION
  • Inspect the following connectors and terminals. (See CONNECTOR INSPECTION .)
    • Coupling component temperature sensor
    • Differential oil temperature sensor
    • AWD solenoid
      • Electrical supply unit (ESU)
  • Are the connector and terminal normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
5 INSPECT AWD SOLENOID FOR MALFUNCTION
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See COUPLING COMPONENT REMOVAL/INSTALLATION (US) .)
6 VERIFY ELECTRICAL SUPPLY UNIT (ESU) DTCs
  • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION .)
  • Are any electrical supply unit (ESU) DTCs displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [BODY CONTROL MODULE (BCM) (US)] .)
No Go to the next step.
7 INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION
  • Inspect the following connectors and terminals. (See ELECTRICAL SUPPLY UNIT (ESU) INSPECTION .)
    • Coupling component temperature sensor
    • Differential oil temperature sensor
      • AWD solenoid
  • Are all the connectors and terminals normal?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification 1 VERIFY THAT VEHICLE IS REPAIRED
  • Clear the DTC recorded in the memory. (See CLEARING DTC .)
  • Replicate the vehicle conditions at the time the DTC was detected using the following procedure.
    • Switch the ignition ON (engine off)
  • Perform the DTC inspection for the PCM. (See DTC INSPECTION .)
  • Is the same Pending DTC present?
Yes Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW (US) .)
If the CAN communication is normal, perform the diagnosis from Step 1.
No Go to the next step.
Repair completion verification 2 VERIFY IF OTHER DTCs DISPLAYED
  • Perform the DTC inspection. (See DTC INSPECTION .)
  • Are any other DTCs displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
No DTC troubleshooting completed.