STEP 1. Scan tool MB991958 CAN bus diagnostics
STEP 2. Check whether the DTC is reset after repairing the CAN bus line.
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position and hold there for 2 seconds.
(3) Fully depress the accelerator pedal, and maintain its position for 2 seconds.note | The coupling coil electronic control is also based on the accelerator pedal opening degree, thus the signal is sent to the ECU. |
(4) Check if the DTC is set.
Is the DTC C145A set?
Go to Step 3. The procedure is complete.
STEP 3. Scan tool MB991958 data list
STEP 4. Check the following connector:
STEP 5. Wiring harness check
STEP 6. Resistance measurement between electronic control coupling solenoid connector (coupling side) terminals
STEP 7. Voltage measurement at the AWD-ECU connector
(1) Disconnect the C-228 AWD-ECU connector.
(2) 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 8. Go to Step 9.
STEP 8. Wiring harness check
STEP 9. Wiring harness check
STEP 10. Check whether the DTC is reset.
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position and hold there for 2 seconds.
(3) Fully depress the accelerator pedal, and maintain its position for 2 seconds.note | The coupling coil electronic control is also based on the accelerator pedal opening degree, thus the signal is sent to the ECU. |
(4) Check if the DTC is set.
Is the DTC C145A set?
Replace AWD-ECU (Refer to ). Then go to Step 11. The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).
STEP 11. Check whether the DTC is reset.
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position and hold there for 2 seconds.
(3) Fully depress the accelerator pedal, and maintain its position for 2 seconds.note | The coupling coil electronic control is also based on the accelerator pedal opening degree, thus the signal is sent to the ECU. |
(4) Check if the DTC is set.
Is the DTC C145A set?
Diagnose again from Step 1. The procedure is complete.