Traction Control System (Tcl)
DTC C1276: Power Supply Circuit Failure of ValvesSolenoid Valve And Motor Power Supply Circuit:
CAUTION: 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.
CIRCUIT OPERATION
^ The ABS/TCL-ECU contains the power supply circuit (terminal 32) for the solenoid valve. The solenoid valve is energized by the valve relay, which is integrated in the ABS/TCL-ECU.
^ The valve relay, which is integrated in the ABS/TCL-ECU, is always energizing the solenoid valve unless the initial check is in progress when the ignition switch is turned on.
ABS/TCL DTC SET CONDITIONS
This diagnostic trouble code will be set under the cases below.
^ After the ABS/TCL-ECU turned on the valve relay, the solenoid valve is not energized (valve relay OFF failure).
CAUTION: 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.
CIRCUIT OPERATION
^ The ABS/TCL-ECU contains the power supply circuit (terminal 32) for the solenoid valve. The solenoid valve is energized by the valve relay, which is integrated in the ABS/TCL-ECU.
^ The valve relay, which is integrated in the ABS/TCL-ECU, is always energizing the solenoid valve unless the initial check is in progress when the ignition switch is turned on.
ABS/TCL DTC SET CONDITIONS
This diagnostic trouble code will be set under the cases below.
^ After the ABS/TCL-ECU turned on the valve relay, the solenoid valve is not energized (valve relay OFF failure).
DIAGNOSIS
Required Special Tools:
^ MB991958: Scan Tool (MUT-III Sub Assembly)
^ MB991824: V.C.I.
^ MB991827: MUT-III USB Cable
^ MB991910: MUT-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 tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
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. Then go to Step 2.
STEP 2. Recheck for diagnostic trouble code.
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.
1. Turn the ignition switch to the "ON" position.
2. Erase the DTC.
3. Turn the ignition switch to the "LOCK" (OFF) position.
4. Turn the ignition switch to the "ON" position.
5. Check if the DTC is set.
6. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC C1276 set?
YES: Replace the hydraulic unit (integrated with ABS/TCL-ECU).
NO: The procedure is complete.