C1236

Circuit Description
The EBCM monitors the system voltage level available for system operation. A low voltage condition prevents the system from operating properly.

Conditions for Running the DTC
^ The vehicle speed is greater than 8 km/h (5 mph).
^ The ignition voltage is less than 10.5 volts.
^ The system relay is commanded ON.

Conditions for Setting the DTC
One of the following conditions exists for 0.72 seconds:
^ During initialization or when the system is not in ABS/TCS/VSES the system voltage is less than 10.5 volts.
^ When the system is in ABS/TCS/VSES, the system voltage is less than 9.0 volts.

Action Taken When the DTC Sets
If equipped, the following actions occur:
^ The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle. The ABS indicator turns ON. The TRAC OFF indicator turns ON.
^ The DIC displays the SERVICE STABILITY SYSTEM message.
^ The DRP does not function optimally, or with ignition voltage less than 8.5 volts, the EBCM disables the DRP.
^ When the EBCM disables the DRP, the following actions also occur:
- DTC C1248 sets.
- The red BRAKE warning indicator turns ON.

Conditions for Clearing the DTC
^ The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function.
^ The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids
^ Test the charging system. Refer to A Diagnostic System Check - Starting and Charging in Engine Electrical.
^ Possible causes of this DTC are the following conditions:
^ A charging system malfunction
^ An excessive battery draw
^ A weak battery
^ A faulty system ground

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step uses the scan tool to inspect the system voltage to the EBCM.
3. This step measures the battery positive voltage circuit.
4. This step tests the module ground circuit.