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Home >> Mazda >> 2017 >> CX-3 Touring, AWD >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (4 Of 5) >> DTC U0074-00; CAN System Communication Error (Local CAN Between PCM And TCM) >> Diagnostic Procedure
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Diagnostic Procedure

DTC U0074-00; CAN SYSTEM COMMUNICATION ERROR (LOCAL CAN BETWEEN PCM AND TCM) - 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 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 VERIFY RELATED PENDING CODE AND/OR DTC
  • Switch the ignition off, then ON (engine off).
  • Perform the Pending Trouble Code Access Procedure and DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.0] .)
  • Are any other PENDING CODEs and/or DTCs present?
Yes Go to the applicable PENDING CODE or DTC inspection.
(See DTC TABLE [SKYACTIV-G 2.0] .)
No Go to the next step.
4 CONFIRM TCM DTC Yes DTC U0074:00 or U0115:00 is displayed:
No TCM can be considered the cause.
  • Replace the control valve body, then go to the next step. (See CONTROL VALVE BODY REMOVAL/INSTALLATION [EW6A-EL/EW6AX-EL].)
5 VERIFY DTC TROUBLESHOOTING COMPLETED Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.0] .)
No Go to the next step.
6 VERIFY AFTER REPAIR PROCEDURE Yes Go to the applicable DTC inspection.
(See DTC TABLE [SKYACTIV-G 2.0] .)
No DTC troubleshooting completed.