C0800

DTC C0800: Low Voltage Fault





Circuit Description
Proper operation of the Electronic Brake Control Module (EBCM) requires a certain minimum voltage. The EBCM monitors the ignition feed circuit to determine if the voltage falls below a minimum level.

Diagnosis
This test checks for battery output, proper grounding, blown fuses, faulty ignition switch, and problems in the circuitry.

Cause(s)
- The battery is defective.
- There is a defective ground connection.
- A connector is damaged.
- A wire is broken or shorted.
- A fuse is blown.
- The ignition switch is malfunctioning.

Fail Action
ABS action is disabled during the period of low voltage, and the ABS warning lamp is ON for the remainder of the ignition cycle. If the failure is intermittent, the EBCM will enable the system at the next ignition cycle and set a history DTC C0800.

Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table.
1. This step determines whether there is voltage at the battery and at the high current source.
2. This step checks for voltage at the ignition 1 source.
3. This step begins the check for voltage at the EBCM end of the ABS wiring harness.
4. This step checks for a defective ground connection.
5. This is a check for a defective EBCM connector.

Diagnostic Aids
It is very important to perform a thorough inspection of the wiring and the connectors. Failure to do so may result in misdiagnosis, causing part replacement with a reappearance of the malfunction.

Troubleshooting

Step 1-5:

Step 6-16:

Step 17-23: