STEP 1. Scan tool MB991958 CAN bus diagnostics
STEP 2. Check the following connector:
STEP 3. Voltage measurement at the AWD-ECU connector
(1) Disconnect the C-228 AWD-ECU connector.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between the C-228 wiring harness side connector terminals No.3, No.4 (Ignition switch "ON") and the body ground.OK: System voltage
Is the check result normal?
Go to Step 5. Go to Step 4.
STEP 4. Wiring harness check
STEP 5. Resistance measurement at the AWD-ECU connector
(1) Disconnect the C-228 AWD-ECU connector.
(2) Measure the resistance between the C-228 wiring harness side connector terminals No. 10 and the body ground.OK: Continuity exists (2 ohm or less)
Is the check result normal?
Go to Step 7. Go to Step 6.
STEP 6. Wiring harness check
STEP 7. Retest the system.
STEP 8. Retest the system.