DTC U0073 [MZR-CD (RF Turbo)]

BME010290000203

DTC U0073

CAN BUS OFF

DETECTION CONDITION

• CAN controller is damaged.
Diagnostic support note
• MIL does not come on.
• FREEZE FRAME DATA is not available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Short to ground circuit between DLC-2 terminal E and PCM terminal 39
• Short to power circuit between DLC-2 terminal F and PCM terminal 13
• CAN communication line short each other
• CAN controller damaged.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
• Check for related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to available Service Information.
• If vehicle is not repaired, go to the next step.
No
Go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Check for related Service Bulletins and/or on-line repair information availability.
• Is any related repair information available?
Yes
Perform repair or diagnostic according to available repair information.
• If vehicle is not repaired, then go to the next step.
No
Go to the next step.
3
INSPECT TCM CONNECTOR FOR POOR CONNECTION
• Turn the engine switch off.
• Disconnect the DLC-2 connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair the terminal, then go to Step 8.
No
Go to the next step.
4
CHECK CAN COMMUNICATION LINE FOR SHORT TO GROUND
• Inspect for continuity between the following terminal (wiring harness-side) and body ground:
- DLC-2 connector terminal E
- DLC-2 connector terminal F
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 8.
No
Go to the next step.
5
CHECK CAN COMMUNICATION LINE FOR SHORT TO POWER
• Measure the voltage between the following terminal (wiring harness-side) and body ground:
- DLC-2 connector terminal E
- DLC-2 connector terminal F
• Is the voltage B+?
Yes
Repair or replace the wiring harness, then go to Step 8.
No
Go to the next step.
6
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Turn the engine switch off.
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair the terminal, then go to Step 8.
No
Go to the next step.
7
CHECK CAN COMMUNICATION LINE FOR SHORT TO EACH OTHER
• Inspect for continuity between PCM connector terminal 13 and 39 (wiring harness-side).
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Go to the next step.
8
VERIFY DTC U0073 DETECTED AGAIN
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Turn the engine switch off, then start the engine.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
• Is there any DTC present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.