ABS and Brake Warning Indicators

ABS Warning Indicator and Red Brake Warning Indicator (EBC 2 and EBC 325)

The system is equipped with an amber ABS and a red brake warning indicator to alert the driver of a malfunction it has detected. The CAB can control the operation of both the yellow ABS warning indicator and the red brake warning indicator via CCD BUS.

The CAB controls the ABS warning indicator by making it do one of three things:
^ light steady for 3.4 seconds during an initial test at the beginning of an ignition cycle to function as a bulb check.
^ light steady when a system malfunction exists.
^ light flashing if a vehicle speed signal parameter is faulty or missing.

The amber antilock brake system warning indicator is controlled by the vehicle's "smart" cluster. All Dodge Trucks are equipped with a smart instrument cluster that has direct control over the ABS warning indicator and red brake warning indicator. The cluster will periodically transmit a message over the CCD bus relating to diagnostics and current lamp status for the ABS and red brake indicator. The cluster will expect a periodic message back from the CAB indicating whether the indicator should be turned on or off. In the event that no signal is received from the CAB for a certain number of times, the cluster will turn on the ABS warning indicator. The indicator detects system related problems and takes diagnostic action.

The vehicle instrument cluster has a red BRAKE warning indicator to alert the driver to the following conditions:
^ parking brake applied
^ hydraulic failure in either front or rear channel
^ ABS system malfunction

The red brake warning indicator is controlled by the vehicle's "smart" cluster. There is a parallel path to chassis ground that will illuminate the red brake warning indicator:
^ through the parking brake switch contacts
^ through the brake warning indicator switch
^ through the CAB via CCD Bus

The CAB can control the operation of both the yellow ABS warning indicator and the red brake warning indicator
^ If the CAB is disconnected, the yellow indicator will be illuminated.
^ If the axle type or tire size are not programmed properly, the yellow indicator will blink.
^ If a system DTC is set, both the yellow and red indicators will be illuminated.