Diagnostics Item 22

DIAGNOSTIC ITEM 22: Diagnose when the scan tool cannot receive the data sent by radio and CD player [vehicles with radio and CD player].

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 radio and CD player, this diagnosis result will be set.

TROUBLE JUDGMENT CONDITIONS

If a communication flag is not set for the radio and CD player, the ETACS-ECU determines that there is a failure.

TROUBLESHOOTING HINTS

- Malfunction of the connector [joint connector (CAN1), radio and CD player connector improperly connected]

- Malfunction of the wiring harness [open circuit between the radio and CD player connector and the joint connector (CAN1), power supply circuit to the radio and CD player]

- Malfunction of the radio and CD player

DIAGNOSIS

Required Special Tools:

- MB991223: Harness Set

- MB992006: Extra Fine Probe

STEP 1. Check joint connector (CAN1) C-06 and radio and CD player connector C-104 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-06 and radio and CD player connector C-104 in good condition?

YES Go to Step 2.
NO Repair the damaged parts.
STEP 2. Check the wiring harness between joint connector (CAN1) C-06 and radio and CD player connector C-104 for open circuit.

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-06 and radio and CD player connector C-104, and check the wiring harness.





(2)Check the wiring harness between joint connector (CAN1) C-06 (terminal 6) and radio and CD player connector C-104 (terminal 23)
OK: Continuity exists (2 ohms or less)






(3)Check the wiring harness between joint connector (CAN1) C-06 (terminal 17) and radio and CD player connector C-104 (terminal 33)
OK: Continuity exists (2 ohms or less)

Q. Is the wiring harness between joint connector (CAN1) C-06 and radio and CD player connector C-104 in good condition?

YES Check the power supply circuit of the radio and CD player. Symptom Chart.

NO Repair the wiring harness between joint connector (CAN1) C-06 and radio and CD player connector C-104.