Operation CHARM: Car repair manuals for everyone.

HVAC Control

CIRCUIT OPERATION
Battery voltage for the HVAC control is supplied on circuit A22. This circuit is HOT in the RUN position only and connects from the ignition switch to the HVAC control.

Circuit A2 supplies voltage to the ignition switch. This circuit is protected by a 10 Amp fuse located in cavity 8 of the junction block.

Power for the A2 circuit is supplied on circuit A6. This circuit is protected by a 40 Amp fuse located in cavity 6 of the Power Distribution Center (PDC).

Ground for the HVAC control is supplied on circuit Z2. This ground terminates at the instrument panel ground.

The Z2 circuit is spliced internal to the HVAC control and supplies the ground path for the other switches and indicators in the switch pod, in addition the Z2 circuit supplies ground for the temperature control(s), and mode select switch.

The HVAC control uses resistors in the temperature control(s) and the mode switch to determine operators request.