Keyless Operation System (KOS)

DTC U0151: SRS-ECU CAN time-out

CAUTION:

- If DTC U0151 is set, be sure to diagnose the CAN bus line.
- When replacing the ECU, always check that the communication circuit is normal.

DIAGNOSTIC FUNCTION

If no signal from SRS-ECU can be received, KOS-ECU sets diagnostic trouble code No. U0151.

TROUBLESHOOTING HINTS

- The CAN bus line may be defective
- The SRS-ECU may be defective
- Malfunction of KOS-ECU

DIAGNOSIS

Required Special Tools:

- 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

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





(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (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 ignition switch to the "ON" position.
(3)Diagnose the CAN bus line.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

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).

STEP 2. Using scan tool MB991958, read the SRS-ECU diagnostic trouble code

Check again if the DTC is set to the SRS-ECU.

Q. Is the DTC set?

YES Troubleshoot the SRS Supplemental Restraint System).
NO Go to Step 3.
STEP 3. Using scan tool MB991958, read the other system diagnostic trouble code.

Check if DTC U0151 is set to the combination meter.

Q. Is the DTC set?

YES Go to Step 4.
NO Go to Step 5.
STEP 4. Recheck for diagnostic trouble code.

Check again if the DTC is set to the KOS-ECU.

(1)Erase the DTC.

(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.

(3)Check if DTC is set.

(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the DTC set?

YES Replace the SRS-ECU.
NO The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
STEP 5. Recheck for diagnostic trouble code.

Check again if the DTC is set to the KOS-ECU.

(1)Erase the DTC.

(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.

(3)Check if DTC is set.

(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the DTC set?

YES Replace KOS-ECU and register the ID codes (Refer to ID registration procedure manual - ID codes registration judgement table).
NO The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).