C1618

DTC C1618: AWC CAN Local Data System (data not received)

G AND YAW RATE SENSOR POWER SUPPLY

Refer to S-AWC (Super All Wheel Control).

CAUTION:

- If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
- Do not drop the G and yaw rate sensor or subject it to a shock.
- When G and yaw rate sensor is replaced, calibrate G and yaw rate sensor (refer to On-vehicle Service G and Yaw Rate Sensor Calibration ), and initialize the lateral/longitudinal acceleration correction amount stored in AWC-ECU. (Refer to item No.2: Lateral acceleration correction amount initialization, and No.3: Longitudinal acceleration correction amount initialization Actuator Test Reference Table .)

OPERATION

AWC-ECU receives various data from ASC-ECU, G and yaw rate sensor via the local CAN communication.

DTC SET CONDITIONS

The code is set when the signal necessary for AWC control cannot be received.

PROBABLE CAUSES

- The CAN bus line is defective.
- Malfunction of local CAN bus line
- Malfunction of ASC-ECU
- Malfunction of G and yaw rate sensor
- Malfunction of AWC-ECU

DIAGNOSTIC PROCEDURE

STEP 1. Scan tool CAN bus diagnostics

Using scan tool MB991958, diagnose the CAN bus lines.

Q. Is the check result normal?

YES Go to Step 3.
NO Repair the CAN bus lines. CAN Bus Diagnostics Chart.) After repairing the CAN bus line, go to Step 2.
STEP 2. Check whether the DTC is reset.

Q. Is DTC No. C1618 set?

YES Go to Step 3.
NO This diagnosis is complete.
STEP 3. Scan tool diagnostic trouble code

Check if the AWC diagnostic trouble code No. U1003 is set.(Refer to Super All Wheel Control (S-AWC).)

Q. Is the DTC set?

YES Perform the relevant troubleshooting.
NO Go to Step 4.
STEP 4. Scan tool diagnostic trouble code

Check the ASC diagnostic trouble code. Active Stability Control System (ASC).)

Q. Is the DTC set?

YES Perform the relevant troubleshooting.
NO Go to Step 5.
STEP 5. ASC-ECU connector, G and yaw rate sensor connector, AWC-ECU connector, intermediate connector check: A-05, C-38, C-46, C-47

Q. Is the check result normal?

YES Go to Step 6.
NO Repair the defective connector. Then go to Step 10.
STEP 6. Check the wiring harness between C-46 AWC-ECU connector terminal No. 9, 10 and C-38 G and yaw rate sensor connector terminal No. 2, 3, and between C-46 AWC-ECU connector terminal No. 9, 10 and A-05 ASC-ECU connector terminal No. 18, 19.

Check the wiring harness for open and short circuit (to ground, to power supply, or line-to line).

Q. Is the check result normal?

YES Go to Step 7.
NO Repair the wiring harness. Then go to Step 9.
STEP 7. Scan tool service data

Check the following service data. (Refer to Data List Reference Table.)

- Item No. 26: Yaw rate sensor
- Item No. 29: Lateral G sensor
- Item No. 31: Longitudinal G sensor

Q. Is the check result normal?

YES Go to Step 9.
NO Go to Step 8.
STEP 8. Check the wiring harness between A-05 ASC-ECU connector terminal No. 22 and C-38 G and yaw rate sensor connector terminal No. 1, and between A-05 ASC-ECU connector terminal No. 29 and C-38 G and yaw rate sensor connector terminal No. 5.

Check the wiring harness for open or short circuit (short to ground).

Q. Is the check result normal?

YES Replace the G and yaw rate sensor. Service and Repair.) Then go to Step 9.
NO Repair the wiring harness. Then go to Step 10.
STEP 9. Check whether the DTC is reset.

Q. Is DTC No. C1618 set?

YES Replace the AWC-ECU.(Refer to Active Center Differential (ACD).) Then go to Step 10.
NO Intermittent malfunction. How to Cope With Intermittent Malfunctions.)
STEP 10. Check whether the DTC is reset.

Q. Is DTC No. C1618 set?

YES Return to Step 1.
NO This diagnosis is complete.