For 1990-2009 cars

### Fuses

IGN3 Fuse

Location: IPJB

Type: 10A Minifuse

Feeds: Circuit 641 and RR DEFOG relay coil

If one of the following systems is operating normally, the fuse is most likely good.

Circuits fed by the HVAC fuse:

• | Generator

• | Power windows

• | A/C

• | DRL

If the fuse is blown determine the cause of the blown fuse and repair.

Replace fuse as needed.

RR DEFOG Fuse

Location: UHJB

Type: 30A Minifuse

Feeds: Circuit 1240

If one of the following systems is operating normally, the fuse is most likely good.

• | Rear defog relay

• | Rear defog element

If the fuse is blown determine the cause of the blown fuse and repair.

Replace fuse as needed.

### Grounds

Before checking the ground circuit from the switch all the way to the ground stud, check the circuit from the splice pack to ground by testing some of the other subsystems grounded by the same splice pack. If the other subsystems function properly, it is most likely that the path from the splice pack to ground is good, or at least one of the paths is good with redundantly ground splice packs.

I/P Splice Pack #1

Location: Taped to harness behind I/P cluster.

The systems grounded to I/P splice Pack #1 are grounded redundantly with I/P Splice Pack #2 at ground point location D, I/P chassis ground. If one of the following systems is operating normally, the ground circuit is most likely good.

• | The eransaxle shift program switch

• | The I/P dimmer

• | The cruise control

• | The cigar lighter element

Check for OPENS/SHORTS

Repair as needed.

Left Rear Body Ground Splice Pack

Location: Behind left rear shock tower.

The Left Rear Body Ground Splice Pack provides a ground path for the rear body and liftgate harnesses. If one of the following systems is operating normally, the ground circuit is most likely good.

• | License, CHMSL, cargo lamps

• | Fuel pump

• | Washer pump (Wagon)

Check for OPENS/SHORTS

Repair as needed.

### Components

RR Defog Relay

The window RR Defog, fog lamp and A/C relays are interchangeable with each other.

Substitute another relay to see if the problem is fixed.

Repair/replace as needed.

Rear Defog Switch (Part of POD Switches)

Check the defogger ON indicator. It should light when the rear defogger switch is ON. The indicator should not be lit with the rear defogger switch OFF.

The RR Defog relay should click when the rear defog switch is turned ON and click again when the rear defogger system times out or is turned OFF.

Check rear defog switch resistance.

Switch resistance: Open when rear defogger is OFF. Less than 1 ohm when rear defog switch is pressed ON.

If the ON indicator has failed the whole switch must be replaced. If the dimming bulb has failed, it can be replaced separately.