C1236

CIRCUIT DESCRIPTION
This circuit monitors the voltage level available to the Electronic Brake Control Module/Electronic Brake Traction Control Module (EBCM/EBTCM). If the voltage drops below 10.5 volts, full performance of the ABS/TCS cannot be guaranteed. During ABS/TCS operation, there are several current requirements that will cause battery voltage to drop. The voltage is monitored prior to ABS/TCS operation in order to indicate good charging system condition and also during ABS/TCS operation when the voltage may drop significantly.

CONDITIONS FOR SETTING THE DTC
The vehicle speed is greater than 8 km/h (5 mph) and the battery and ignition voltages are less than 10.5 volts

ACTION TAKEN WHEN THE DTC SETS
^ A DTC C1236 is stored
^ The ABS/TCS is disabled
^ The ABS and TRACTION OFF indicators are turned on

CONDITIONS FOR CLEARING THE DTC
^ The condition for the Diagnostic Trouble Code (DTC) is no longer present and the scan tool clear DTC function is used
^ 50 ignition cycles have passed with no DTCs detected

DIAGNOSTIC AIDS
^ Thoroughly inspect the wiring and the connectors. Failure to carefully and fully inspect the wiring and the connectors can result in misdiagnosis. Misdiagnosis may cause replacement of parts without repairing the malfunction.
^ Inspect for other low voltage conditions. Test the charging system. Refer to Starting and Charging.
^ The following conditions are other possible causes of low system voltage:
- A charging system malfunction
- Excessive parasitic drain
- A weak battery
- A faulty system ground
^ If an intermittent malfunction exists, refer to Troubleshooting Procedures.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
4. This step checks for a good ground.
6. This step checks for battery voltage.