23A-DIAGNOSTIC FUNCTION

DIAGNOSIS FUNCTION

When the system fails

"AWD SYSTEM SERVICE REQUIRED" should be displayed at the center on the multi-information display, and "AWD" should flash at the left upper.

When the S-AWC system oil is too hot
<Up to 20 Model year>

Either of "AUTO", "SNOW", "GRAVEL" should flash at the left upper, and "AWD SYSTEM OVERHEATING SLOW DOWN" should be displayed at the center. Then the S-AWC drive mode-selector will be disabled to avoid damage to the drive train components.

Either of "NORMAL", "SNOW", "GRAVEL" should flash at the left upper, and "AWD SYSTEM OVERHEATING SLOW DOWN" should be displayed at the center. Then the S-AWC drive mode-selector will be disabled to avoid damage to the drive train components.

Fail-safe function

If the AWC-ECU receives an abnormal signal from sensors, switches, or solenoids, it will enter a fail-safe mode to ensure the safety of the driver and prevent damage to the system.

Fail-safe reference table

Diagnostic trouble code No.	Control content
C1613, C1614	The multi-information display should inform the driver of a system malfunction, but the vehicle handling will not be affected. The S-AWC will continue to work.
C1219, C121A, C123C, C1242, C1623, C1630, C1632, C1633, C2205, U0100, U0101, U0126, U0401, U1425, U1426	The multi-information display should inform the driver of a system malfunction, and the system control will be disabled partially.
C1621	"AWD SYSTEM OVERHEATING SLOW DOWN" will be displayed on the multi-information display, and the system will protect the drive train components.
C100A, C1011, C1014, C1015, C101C, C101F, C1020, C1027, C102A, C102B, C1032, C1035, C1078, C1610, C1615, C1616, C1624, C1626, C1628, C1629, C1631, C1707, C2100, C2101, U0121, U0141, U0431, U1073, U1195	The multi-information display should inform the driver of a system malfunction, and the system will be disabled.

note	When the ignition switch is turned from OFF to ON, all of the fail-safe controls will be resumed. In the case where the failure is not confirmed, AWC-ECU may stop the control or stop part of the control without displaying the system malfunction in the multi-information display.

ON-BOARD DIAGNOSTICS

If the AWC-ECU detects any problem in the CAN communication line or the ECUs, which the AWC-ECU is communicating with, it sets a diagnostic trouble code. The diagnostic trouble codes can be confirmed by connecting the scan tool (M.U.T.-IIISE). The set diagnostic trouble codes are not erased even after the ignition switch has been turned to the LOCK (OFF) position, or the battery has been disconnected. The diagnostic trouble codes can be erased by operating the scan tool (M.U.T.-IIISE).

HOW TO CONNECT THE SCAN TOOL (M.U.T.-IIISE)

Required Special Tools:

MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
MB992745: V.C.I.-Lite main harness A
MB992747: V.C.I.-Lite USB cable short
MB992748: V.C.I.-Lite USB cable long

caution

To prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).

Ensure that the ignition switch is at the "LOCK" (OFF) position.

2. Start up the personal computer.

3. Connect special tool MB992747/M992748 to special tool MB992744 and the personal computer.

4. Connect special tool MB992745 to special tool MB992744.

5. Connect special tool MB992745 to the data link connector.

note	When the special tool MB992745 is connected to the data link connector, the special tool MB992744 indicator light will be illuminated in a green color.

6. Start the M.U.T.-IIISE system on the personal computer.

note	Disconnecting scan tool (M.U.T.-IIISE) is the reverse of the connecting sequence, making sure that the ignition switch is at the "LOCK" (OFF) position.

HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODES

Required Special Tools:

MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
MB992745: V.C.I.-Lite main harness A
MB992747: V.C.I.-Lite USB cable short
MB992748: V.C.I.-Lite USB cable long

note	If the battery voltage is low, diagnostic trouble codes will not be set. Check the battery if scan tool (M.U.T.-IIISE) does not display.

Connect scan tool (M.U.T.-IIISE) to the data link connector.

2. Turn the ignition switch to the "ON" position.

3. Select "STV."

4. Select "AWC."

5. Select "Diagnostic Trouble Code" to read the DTC.

6. If a DTC is set, it is shown.

7. Choose "Erase DTCs" to erase the DTC.

HOW TO READ DATA LIST

Required Special Tools:

MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
MB992745: V.C.I.-Lite main harness A
MB992747: V.C.I.-Lite USB cable short
MB992748: V.C.I.-Lite USB cable long

1. Connect scan tool (M.U.T.-IIISE) to the data link connector.

2. Turn the ignition switch to the "ON" position.

3. Select "STV."

4. Select "AWC."

5. Select "Data List."

6. Choose an appropriate item and select the "OK" button.

HOW TO PERFORM ACTUATOR TEST

Required Special Tools:

MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
MB992745: V.C.I.-Lite main harness A
MB992747: V.C.I.-Lite USB cable short
MB992748: V.C.I.-Lite USB cable long

1. Connect scan tool (M.U.T.-IIISE) to the data link connector.

2. Turn the ignition switch to the "ON" position.

3. Select "STV."

4. Select "AWC."

5. Select "Actuator Test."

6. Choose an appropriate item and select the "OK" button.

HOW TO DIAGNOSE THE CAN BUS LINES

Required Special Tools:

MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
MB992745: V.C.I.-Lite main harness A
MB992747: V.C.I.-Lite USB cable short
MB992748: V.C.I.-Lite USB cable long

1. Connect scan tool (M.U.T.-IIISE) to the data link connector.

2. Turn the ignition switch to the "ON" position.

3. Select "CAN bus diagnosis" from the start-up screen.

4. When the optional equipment screen is displayed, choose the one which the vehicle is fitted with, and then select the "OK" button.