27C-DIAGNOSIS FUNCTION

DIAGNOSTIC FUNCTION

When the system fails

"4WD SERVICE REQUIRED" should be displayed at the center on the multi-information display, and "4WD" should flash at the left upper.

When the AWD system oil is too hot

Either of "4WD ECO", "4WD AUTO" or "4WD LOCK" should flash at the left upper, and "4WD SYSTEM OVERHEATING SLOW DOWN" should be displayed at the center. Then the drive mode selector will be disabled to avoid damage to the drive train components.

Fail-safe function

If the AWD-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

DTC 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 electronic controlled AWD will continue to work.
C1219, C121A, C123C, C1242, C1630, C1632, C1633, C2205, U0100, U0101, U0126, U0401, U0428, U1425, U1426, U1428	The multi-information display should inform the driver of a system malfunction, and the system control will be disabled partially.
C1621	"4WD SYSTEM OVERHEATING" 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, C1616, C1624, C1626, C1628, C1629, C1631, C1707, C2100, C2101, U0141, U0431, U1073, U1195, U1427	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.

ON-BOARD DIAGNOSTICS

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

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

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
MB991958: Scan Tool (M.U.T.-III Sub Assembly)

MB991824: Vehicles Communication Interface (V.C.I.)
MB991827: M.U.T.-III USB Cable
MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

caution

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

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

2. Start up the personal computer.

3. Connect special tool MB992747/M992748 or special tool MB991827 to special tool MB992744 or special tool MB991824 and the personal computer.

4. Connect special tool MB992745 or special tool MB991910 to special tool MB992744 or special tool MB991824.

5. Connect special tool MB992745 or special tool MB991910 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. Turn the power switch of special tool MB991824 to the "ON" position. <When using the special tool MB991824>

note	When special tool MB991824 is energized, special tool MB991824 indicator light will be illuminated in a green color.

7. Start the M.U.T.-III system on the personal computer.

note	Disconnecting scan tool (M.U.T.-III) 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
MB991958: Scan Tool (M.U.T.-III Sub Assembly)

MB991824: Vehicles Communication Interface (V.C.I.)
MB991827: M.U.T.-III USB Cable
MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

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

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

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

3. Select "System select" from the start-up screen.

4. Select "From 2006 MY" of "Model Year." When the "Vehicle Information" is displayed, check the contents.

5. Select "AWC" from "System List," and press the "OK" button.

note	When the "Loading Option Setup" list is displayed, check the applicable item.

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

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

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

HOW TO READ DATA LIST

Required Special Tools:

MB992744: Vehicle communication interface-Line (V.C.I.-Line)
MB992745: V.C.I.-Line main harness A (for vehicle with CAN communication)
MB992747: V.C.I.-Line USB cable short
MB992748: V.C.I.-Line USB cable long
MB991958: Scan Tool (M.U.T.-III Sub Assembly)

MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: M.U.T.-III USB Cable
MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

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

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

3. Select "System select" from the start-up screen.

4. Select "From 2006 MY" of "Model Year." When the "Vehicle Information" is displayed, check the contents.

5. Select "AWC" from "System List," and press the "OK" button.

note	When the "Loading Option Setup" list is displayed, check the applicable item.

6. Select "Data List."

7. 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
MB991958: Scan Tool (M.U.T.-III Sub Assembly)

MB991824: Vehicles Communication Interface (V.C.I.)
MB991827: M.U.T.-III USB Cable
MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

1. Connect scan tool (M.U.T.-III) 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 vehicle information is displayed, confirm that it matches the vehicle being diagnosed.

If they match, go to Step 8.
If not, go to Step 5.

5. Select the "view vehicle information" button.

6. Enter the vehicle information and select the "OK" button.

7. When the vehicle information is displayed, confirm again that it matches the vehicle being diagnosed.

If they match, go to Step 8.
If not, go to Step 5.

8. Select the "OK" button.

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