Diagnostic Item 6
DIAGNOSTIC ITEM 6: Diagnose When The Scan Tool Cannot Receive The Data Sent By AWC-ECU.CAUTION: When servicing a CAN bus line, ground yourself by touching a metal object such as an unpainted water pipe. If you fail to do so, a component connected to the CAN bus line may be damaged.
CAN-C Communication Circuit [M/T]:
CAN-C Communication Circuit [TC-SST]:
FUNCTION
If the scan tool MB991958 cannot communicate with the AWC-ECU, this diagnosis result will be set.
TROUBLE JUDGMENT CONDITIONS
If a communication flag is not set for the AWC-ECU, the ETACS-ECU determines that there is a failure.
TROUBLESHOOTING HINTS
- Malfunction of the connector [joint connector (CAN2), AWC-ECU connector or intermediate connector failed improperly connected]
- Malfunction of the wiring harness [open circuit between the AWC-ECU and the joint connector (CAN2), power supply circuit to the AWC-ECU]
- Malfunction of the AWC-ECU
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Check joint connector (CAN2) C-104 and AWC-ECU connector C-46 and intermediate connector C-41 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
CAUTION: The strand end of the twisted wire should be within 10 cm (4 inches) from the connector.
Q: Are joint connector (CAN2) C-104 and AWC-ECU connector C-46 and intermediate connector C-41 in good condition?
YES : Go to Step 2.
NO : Repair the damaged parts.
STEP 2. Check the wiring harness between joint connector (CAN2) C-104 and AWC-ECU connector C-46 for open circuit.
CAUTION: Strictly observe the specified wiring harness repair procedure.
1. Disconnect joint connector (CAN2) C-104 and AWC-ECU connector C-46, and check the wiring harness.
2. Check the wiring harness between joint connector (CAN2) C-104 (terminal 5) and AWC-ECU connector C-46 (terminal 4)
OK: Continuity exists (2 ohms or less)
3. Check the wiring harness between joint connector (CAN2) C-104 (terminal 16) and AWC-ECU connector C-46 (terminal 5)
OK: Continuity exists (2 ohms or less)
Q: Is the wiring harness between joint connector (CAN2) C-104 and AWC-ECU connector C-46 in good condition?
YES : Check the power supply circuit of the AWC-ECU. Refer to Troubleshooting [S-AWC]. Diagnostic Trouble Code Descriptions
NO : Repair the wiring harness between joint connector (CAN2) C-104 and AWC-ECU connector C-46.