Wireless Control Module (WCM)
DTC U0151: SRS-ECU CAN timeoutCAUTION:
- 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, WCM sets diagnostic trouble codeU0151.
TROUBLESHOOTING HINTS
- The CAN bus line may be defective
- The SRS-ECU may be defective
- Malfunction of WCM
DIAGNOSIS
Required Special Tools:
- 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
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan toolMB991958.
1. Connect scan tool MB991958. Refer to "How to connect the Scan Tool(M.U.T.-III)." Scan Tool Connecting
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 (Refer to Controller Area Network, Diagnosis).
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 (Refer to Troubleshooting). Diagnostic Trouble Code Descriptions
NO: Go to Step 3.
STEP 3. Recheck for diagnostic trouble code.
Check again if the DTC is set to the WCM.
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 WCM and register the ID codes (Refer to ID Codes Registration Judgment Table).
NO: The trouble can be an intermittent malfunction (Refer to General (Body and Chassis) - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).