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For 1990-2009 cars only

Exterior Lights Diagnosis Turn/Hazard/Stop Lamps

Fuses

BRAKE Fuse

Location: Underhood junction block

Type: 15A Minifuse

Feeds: Circuit 540

If the following system is operating, the fuse is most likely good:

    • Brake lamps
    • Center high-mounted stop lamp

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

Replace the fuse as needed.

HAZARD Fuse

Location: Underhood junction block

Type: 10A Minifuse

Feeds: Circuit 1040B

If the following system is operating, the fuse is most likely good:

    • I/P cluster high beam telltale
    • Hazard lamps

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

Replace the fuse as needed.

TURN Fuse

Location: Instrument panel junction block

Type: 10A MaxiFuse

Feeds: Circuit 139

If one of the following systems are operating, the fuse is most likely good:

    • Hazard lamps
    • Turn signal lamps
    • I/P cluster turn indicators

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

Replace the fuse as needed.

Grounds

Before checking the ground circuit from the faulty component 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 grounded splice packs.

I/P Splice Pack #1

Location: Taped to I/P harness behind I/P cluster

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

    • I/P dimmer
    • Cruise control
    • Headlamp switch
    • Cigar lighter element

Check for OPENS/SHORTS.

Repair as needed.

I/P Splice Pack #2

Location: Taped to I/P harness behind I/P cluster

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

    • Fuel level sensor
    • Park brake switch
    • Wiper motor
    • Radio

Check for OPENS/SHORTS.

Repair as needed.

Left Rear Body Ground Splice Pack

Location: See the Ground Distribution section in this manual.

The left rear body ground splice pack provides a ground path for the rear body, deck lid, and lift gate 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.

Right Forward Lamp Splice Pack

Location: Behind right front headlamp

The right forward lamp splice pack provides a ground path for the right side of the forward lamp harness. If one of the following systems is operating normally, the ground circuit is most likely good:

    • Washer pump
    • All right side forward lamps

Check for OPENS/SHORTS.

Repair as needed.

Exterior Lights Diagnosis Park/Marker/License Lamps

Fuses

PARK Fuse

Location: Underhood junction block

Type: 10A Minifuse

Feeds: Circuit 240

If the following system is operating, the fuse is most likely good:

All lighting, except for high/low beam headlamps

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

Replace the fuse as needed.

Grounds

Before checking the ground circuit from the faulty component 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 grounded splice packs.

Right Side Forward Lamp Splice Pack

Location: Behind right front headlamp

The right side forward lamp splice pack provides a ground path for the right side of the forward lamp harness. If one of the following systems is operating normally, the ground circuit is most likely good:

    • Washer pump
    • All right side forward lamps

Check for OPENS/SHORTS.

Repair as needed.

Left Rear Body Ground Splice Pack

Location: See the Ground Distribution section of this manual.

The left rear body ground splice pack provides a ground path for the rear body, deck lid, and lift gate harnesses. If one of the following systems is operating normally, the ground circuit is most likely good:

    • License lamps
    • Fuel pump
    • Rear washer pump -- Wagon

Check for OPENS/SHORTS.

Repair as needed.

Components

Bulbs

Visually inspect the bulb. Check the resistance through the bulb.

Replace as needed.

Headlamp Switch

Refer to Lever Combination Switch (LCS) for testing.

Repair/replace as needed.

Exterior Lights Diagnosis Back Up Lamps

Fuses

B/U LP Fuse

Location: UHJB

Type: 10A Minifuse

Feeds: Circuit 239 and 239A

If the following systems are operating normally, the fuse is most likely good:

    • Backup Bulbs
    • Coolant Level Switch

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

Replace the fuse as needed.

Grounds

Before checking the ground circuit from the faulty component 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 grounded splice packs.

Left Rear Body Ground Splice

The left rear body ground splice pack provides a ground path for the rear body and hatch harness. If one of the following systems is operating normally the ground circuit is most likely good:

    • License, CHMSL, cargo lamps
    • Fuel pump
    • Washer pump

Check for OPENS/SHORTS.

Repair as needed.

Components

Park/Neutral Switch (Back-up Switch) (Auto Trans Only)

  1. Check switch resistance.
  2. Switch resistance: OPEN when PRNDL not in Reverse. Less than one ohm when PRNDL in Reverse.

  3. Repair/replace as needed.

Back Up Switch (Manual Trans Only)

  1. Check switch resistance.
  2. Switch resistance: OPEN when trans not in Reverse. Less than one ohm when PRNDL in Reverse.

  3. Repair/replace as needed.

Bulb Socket

  1. Check voltage through the bulb socket.
  2. Check for damaged or corroded terminals or connectors. Check terminals for tightness.
  3. Repair/replace as needed.