Circuit Operation

CIRCUIT OPERATION
Power for the Anti-Lock Brake (ABS) system is supplied by three fuses. There is a 10 amp fuse located in the Power Distribution Center (PDC) cavity 10. This fuse supplies power to the Controller Anti Lock Brake (CAB), Powertrain Control Module (PCM) and the fuel pump relay on the F12 circuit. Power for the fuse is supplied on the A21 circuit from the ignition switch. This fuse is HOT when the ignition switch is in the START/RUN position.

The second fuse is located in the PDC cavity 13. 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 Modulator and the 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.