Diagnostics Item 23
DIAGNOSTIC ITEM 23: Diagnose when the scan tool cannot receive the data sent by combination meter.
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.
FUNCTION
If the scan tool MB991958 cannot communicate with the combination meter, this diagnosis result will be set.
TROUBLE JUDGMENT CONDITIONS
If a communication flag is not set for the combination meter, the ETACS-ECU determines that there is a failure.
TROUBLESHOOTING HINTS
- Malfunction of the connector [joint connector (CAN1), combination meter connector improperly connected]
- Malfunction of the wiring harness [open circuit between the combination meter connector and the joint connector (CAN1), power supply circuit to the combination meter]
- Malfunction of the combination meter
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Check joint connector (CAN1) C-105 and combination meter connector C-04 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. For details refer to Precautions When CAN Bus Line(s) are Repaired.
Q. Are joint connector (CAN1) C-105 and combination meter connector C-04 in good condition?
YES Go to Step 2.
NO Repair the damaged parts.
STEP 2. Check the wiring harness between joint connector (CAN1) C-105 and combination meter connector C-04.
CAUTION:
Strictly observe the specified wiring harness repair procedure.
For details refer to Precautions When CAN Bus Line(s) are Repaired.
(1)Disconnect joint connector (CAN1) C-105 and combination meter connector C-04, and check the wiring harness.
(2)Check the wiring harness between joint connector (CAN1) C-105 (terminal 3) and combination meter connector C-04 (terminal 14)
(3)Check the wiring harness between joint connector (CAN1) C-105 (terminal 14) and combination meter connector C-04 (terminal 15)
Q. Is the wiring harness between joint connector (CAN1) C-105 and combination meter connector C-04 in good condition?
YES Check the power supply circuit of the combination meter. Symptom Chart.
NO Repair the wiring harness between joint connector (CAN1) C-105 and combination meter connector C-04.