Keyless Operation System (KOS)

DTC U1000: OSS CAN time-out

CAUTION:

- If the diagnosis code No. U1000 is set, diagnose the CAN bus lines.
- When replacing the ECU, always check that the communication circuit is normal.

DIAGNOSTIC FUNCTION

When the signal from OSS-ECU cannot be received, KOS-ECU sets the diagnosis code No.U1000.

TROUBLESHOOTING HINTS

- Malfunction of CAN bus line
- Malfunction of OSS-ECU
- Malfunction of KOS-ECU

DIAGNOSIS PROCEDURE

STEP 1. Using scan tool MB991958, diagnose the CAN bus line

(1)
CAUTION:
To prevent damage to scan tool (MB991958), always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool (MB991958).

Connect scan tool MB991958. Refer to "How to connect the scan tool (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."

(2)Turn the power supply mode of the engine switch to ON.

(3)Diagnose the CAN bus line.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the CAN bus line found to be normal?

YES Go to Step 2.
NO Repair the CAN bus line CAN Bus Diagnostics Chart).
On completion, go to Step 2.
STEP 2. Using scan tool MB991958, read the other system diagnostic trouble code.

Check if DTC U1000 is set to the ETACS-ECU.

Q. Is the DTC set?

YES Go to Step 3.
NO Go to Step 4.
STEP 3. Recheck for diagnostic trouble code.

Recheck if the diagnosis code is set.

(1)Erase the DTC.

(2)Turn the power supply mode of the engine switch from OFF to ON.

(3)Check if DTC is set.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the DTC set?

YES Replace the OSS-ECU.
NO Intermittent malfunction is suspected How to Cope With Intermittent Malfunctions).
STEP 4. Recheck for diagnostic trouble code.

(1)Erase the DTC.

(2)Turn the power supply mode of the engine switch from OFF to ON.

(3)Check if DTC is set.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the DTC set?

YES Replace KOS-ECU and register the ID codes (Refer to ID Codes Registration Procedure).
NO Intermittent malfunction is suspected How to Cope With Intermittent Malfunctions).