ABS
DTC C1242 Abnormality in GCAUTION: If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
OPERATION
The G sensor is incorporated in the ABS-ECU.
DTC SET CONDITIONS
This diagnostic trouble code is set when the abnormality is detected by comparing the G sensor value output from the G sensor with the value output from the wheel speed sensor.
PROBABLE CAUSES
^ Improper installation of the G sensor
^ Malfunction of wheel speed sensor
^ ABS-ECU malfunction
^ External noise interference
^ When the vehicle is driven on a drum roller
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
STEP 1. M.U.T.-III CAN bus diagnostics
Use scan tool to diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 3.
NO: Repair the CAN bus lines. On completion, go to Step 2.
STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines
Q: Is DTC C1242 set?
YES: Go to Step 3.
NO: The procedure is complete.
STEP 3. Check the wheel speed sensor-related diagnostic trouble code.
Use the scan tool to check whether the wheel speed sensor-related diagnostic trouble code is set or not.
Q: Is any DTC set?
YES: Troubleshoot for the relevant diagnostic trouble code.
NO: Go to Step 4.
STEP 4. M.U.T.-III data list
Check the following service data.
^ Item 09: G sensor
Q: Is the check result normal?
YES: Go to Step 5.
NO: Replace the ABS-ECU, and then go to Step 6.
STEP 5. Check whether the diagnostic trouble code is reset.
Q: Is DTC C1242 set?
YES: Replace the ABS-ECU.
NO: Intermittent malfunction.
STEP 6. Check whether the diagnostic trouble code is reset.
Q: Is DTC C1242 set?
YES: Go to Step 1.
NO: The procedure is complete.