S-AWC (Super All Wheel Control)

DTC C2101: Battery Voltage Malfunction (High Voltage)

BATTERY VOLTAGE SYSTEM CIRCUIT

Refer to C2100.

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.

OPERATION

AWC-ECU power supply is provided from the battery via ETACS-ECU.

DTC SET CONDITIONS

The code is set when the AWC-ECU power supply voltage and solenoid valve power supply voltage are 18 V or more.

PROBABLE CAUSES

- Loose battery terminal
- Defective battery
- Charging system failed
- Malfunction of the ETACS-ECU
- Damaged harness wires and connectors
- 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. C2101 set?

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

Check the ETACS diagnostic trouble code. Electronic Time and Alarm Control System (ETACS).)

Q. Is the DTC set?

YES Perform the relevant troubleshooting.
NO Go to Step 4.
STEP 4. Battery terminal check

Check that the battery terminal is not loose.

Q. Is the check result normal?

YES Go to Step 5.
NO Securely install the battery terminal. Then go to Step 5.
STEP 5. Check the battery.

Battery Test.

Q. Is the check result normal?

YES Go to Step 7.
NO Charge or replace the battery. Then go to Step 6.
STEP 6. Check the charging system.

Generator Output Line Voltage Drop Test.

Q. Is the check result normal?

YES Go to Step 7.
NO Repair or replace the charging system component(s).
STEP 7. Voltage measurement at C-46 AWC-ECU connector

Measure the voltage between C-46 AWC-ECU connector terminal No.12 - and the body ground.

OK: Battery positive voltage


Q. Is the check result normal?

YES Go to Step 11.
NO Go to Step 8.
STEP 8. AWC-ECU connector, ETACS-ECU connector check: C-46, C-315

Q. Is the check result normal?

YES Go to Step 9.
NO Repair the defective connector. Then go to Step 12.
STEP 9. Check the wiring harness between C-46 AWC-ECU connector terminal No. 12 and C-315 ETACS-ECU connector terminal No.4.

Check the wiring harness for short circuit (short to power supply).

Q. Is the check result normal?

YES Go to Step 10.
NO Check C-41 intermediate connector. When no problem is found, repair the wiring harness. Then go to Step 12.
STEP 10. Scan tool service data

Item No. 43: Battery voltage (Refer to service data reference table Data List Reference Table.)

Q. Is the check result normal?

YES Intermittent malfunction. How to Cope With Intermittent Malfunctions.)
NO Replace the ETACS-ECU. Electronic Time and Alarm Control System (ETACS) Then go to Step 12.
STEP 11. Scan tool service data

Item No. 43: Battery voltage (Refer to service data reference table Data List Reference Table.)

Q. Is the check result normal?

YES Intermittent malfunction. How to Cope With Intermittent Malfunctions.)
NO Replace the AWC-ECU.(Refer to Active Center Differential (ACD).) Then go to Step 12.
STEP 12. Check whether the DTC is reset.

Q. Is DTC No. C2101 set?

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