Rear Wheel

The vacuum switch is used on the diesel engine only Power for the switch is supplied on circuit A2O. This circuit is HOT in the RUN position only and protected by a 20 amp fuse located in cavity 14 of the fuse block. Ground for the switch is supplied on circuit Z1.

Circuit G9 connects to the vacuum switch and supplies a ground path for circuit G9. If there is a problem in the system, the switch grounds circuit G9 and the red brake warning lamp in the instrument cluster is illuminated.