Circuit Operation

CIRCUIT OPERATION
There are two Anti-Lock Brake Systems (ABS) used in this vehicle.. One is the standard system and the other is equipped with traction control.

Power for either of the Anti-Lock Brake (ABS) system is supplied by three fuses. There is a 15 Amp fuse located in the junction block cavity 4. This fuse supplies power to the ABS controller, Powertrain Control Module (PCM) and the fuel pump relay on the F20 circuit. Power for the fuse is supplied on the A22 circuit from the ignition switch. This fuse is HOT when the ignition switch is in the RUN position.

The second fuse is located in the PDC cavity 19. It is a 40 Amp fuse and used to supply power to the ABS Pump Motor relay on circuit A10. This relay is located in the ABS relay box. The fuse is HOT at all times and powers the contact side of the relay

The third fuse is also located in the PDC cavity 2. It is a 20 Amp fuse and used to power the contact side of the ABS System relay on circuit A20. The fuse is HOT at all times.

There are 3 grounding points used in the ABS system. One is a case ground on the Controller Anti Lock Brake (CAB). The second is on the Z1 circuit from the ABS Hydraulic Control Unit/ABS Relay Box. This ground terminates at the right frame rail.

The third ground is also on the a Z1 circuit from the CAB and terminates at the right frame rail.