How To Proceed With Troubleshooting

UF1AE TRANSFER: FOUR WHEEL DRIVE CONTROL SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

HINT:
The Techstream can be used in steps 3, 4, 5, 7 and 11.

1. VEHICLE BROUGHT TO WORKSHOP
NEXT -- Continue to next step.
2. CUSTOMER PROBLEM ANALYSIS
(a) Confirm problem symptoms.
NEXT -- Continue to next step.
3. CHECK MULTIPLEX COMMUNICATION SYSTEM
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT:
The 4WD control ECU sends the signals from indicator light to the gateway ECU via CAN communication, and the gateway ECU sends the signals to the combination meter assembly via multiplex communication system (BEAN).

Result:






B -- CHECK MULTIPLEX COMMUNICATION CIRCUIT
A -- Continue to next step.
4. CHECK CAN COMMUNICATION SYSTEM
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT:
The ECU of this system is connected to the CAN communication system.
Therefore before starting troubleshooting, make sure to check that there is no trouble in CAN communication system.

Result:






B -- CHECK CAN COMMUNICATION CIRCUIT
A -- Continue to next step.
5. CHECK DTC
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
(1) Record the DTCs.
(b) Clear the DTCs.
(c) Recheck for DTCs.
(1) Simulate the malfunction and check if the DTCs are output again.
Result:






B -- GO TO STEP 10
C -- SYMPTOM SIMULATION
A -- Continue to next step.
6. DTC CHART
NEXT -- Continue to next step.
7. CIRCUIT INSPECTION
NEXT -- Continue to next step.
8. REPAIR
NEXT -- Continue to next step.
9. CONFIRMATION TEST
NEXT -- END
10. PROBLEM SYMPTOMS TABLE
NEXT -- Continue to next step.
11. CIRCUIT INSPECTION
NEXT -- Continue to next step.
12. CONFIRMATION TEST
NEXT -- END