C1214

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Circuit Description
Ignition voltage is supplied to terminal 85 of the Electronic Brake Control relay. The Electronic Brake Control Module (EBCM) is then able to energize the pull-in coil by completing the ground circuit at EBCM terminal D6.The magnetic field created closes the Electronic Brake Control relay contacts and allows battery voltage and current to be supplied to the EBCM. In addition, the EBCM supplies power to the motors and Antilock Brake System (ABS) solenoids.

Conditions for Setting the Diagnostic Trouble Code (DTC)
This DTC will set when the following conditions are met:
- Voltage in the switched battery input circuit to the EBCM falls below 7.05 volts (Circuit (CKT) 9B01).
- This DTC can be set anytime.
- Note: This DTC may take up to 2 seconds to set because it takes time for the Electronic Brake Control relay voltage to decay.

Action Taken When the DTC Sets
- A malfunction DTC stores.
- ABS is disabled.
- The amber ABS warning indicator is turned ON if the rear piston in the motor pack is not expected to be in the home position.

Conditions for Clearing the DTC
- The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.
- 100 drive cycles pass with no DTCs detected. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/in (10 mph), stopping and then turning the ignition OFF.

Diagnostic Aids
The following list contains items that need to be inspected when diagnosing this system:
- Open ABS fuse.
- Faulty Electronic Brake Control relay (contacts open/high resistance).
- Poor harness terminal contacts to the Electronic Brake Control relay (look for spread terminals).
- Faulty electrical circuits (open or high resistance) between the Electronic Brake Control relay and the EBCM (CKT 9B01) and/or between the ABS fuse and the electronic brake control relay (CKT 9A01).
The following conditions may cause an intermittent malfunction:
- A poor connection
- Rubbed-through wire insulation
- A broken wire inside the insulation


Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malt unction. Thoroughly inspect any circuitry that may be causing the intermittent complaint for the following conditions:
- Backed out terminals
- Improper mating
- Improperly formed or damaged terminals
- Poor terminal-to-wiring connections
- Physical damage to the wiring harness

Vibration and Temperature Effects
- Use the following procedure in order to inspect for vibration effects by performing the Relay Test function of the Scan Tool:

1. With the Relay Test commanded on, lightly tap the top and sides of the Electronic Brake Control Relay while monitoring the Electronic Brake Control Relay voltage.
2. If the Electronic Brake Control Relay voltage changes significantly, replace the Electronic Brake Control Relay.

- If DTC C1214 only sets when the vehicle is initially started in cold ambient conditions (temperature less than 0°C - 32°F), replace the Electronic Brake Control Relay.

IMPORTANT: Zero the J 39200 test leads before making any resistance measurements. Refer to the J 39200 user's manual.