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For 1990-2009 cars only

Wiper/Washer System Diagnosis Front

Fuses

Wiper Fuse

Location: IPJB

Type: 25A Minifuse

Feeds: Circuit 143

The fuse feeds the wiper/washer system only.

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 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 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, 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.

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.

    • All right side forward lamps
    • Washer pump

Check for OPENS/SHORTS

Repair as needed.

I/P Splice Pack #2

Location: Taped to harness behind I/P cluster.

The systems grounded to 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.

Circuits

Circuit 92

Battery voltage should be present with ignition in ACC and RUN.

Function: This is the ground wire for the windshield wiper motor/control module in the MIST, INT, LO, and Wash speed positions.

Check for OPENS/SHORTS

Repair as needed.

Circuit 96

Battery voltage should be present with ignition in ACC and RUN.

Function: This is the ground wire for the windshield wiper motor/control module in the HI speed positions.

Check for OPENS/SHORTS

Repair as needed.

Components

Wiper Motor

Check the circuits, connectors, and terminals that are attached to the wiper module.

Check for OPENS/SHORTS

Wiper module should not be tested out of vehicle, it must be connected to the wiper switch to work properly. The internal control module and motor are serviced as one unit and should not be taken apart.

Repair is by replacement only.

If a new wiper motor is installed and the complaint is fixed, install the old motor to verify the problem was in the motor. If the complaint does not appear again, check the terminals and connections for damage, corrosion, and terminal tightness.

Washer Pump

Check the circuits, connectors, and terminals that are attached to the washer module.

Check for OPENS/SHORTS

Disconnect washer pump and connect DVOM between the 2 terminals, 1 and 2, of the harness connector. With the ignition in RUN, activate the washer switch.

    • If battery voltage is measured, all of the circuits and the switch are OK. Replace the washer pump.
    • If the battery voltage is not measured, check the circuits and switch for OPENS/SHORTS.

Repair and replace as needed.

If a new pump is installed and the complaint is fixed, install the old pump to verify the problem was in the pump. If the complaint does not appear again, check the terminals and connections for damage, corrosion, and terminal tightness.

Wiper/Washer System Diagnosis Rear

Fuses

SUN Fuse

Location: IPJB

Type: 15A Minifuse

Feeds: Circuit 580

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

Rear Wiper

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

Replace fuse as needed.

PWR CONVCE Fuse

Location: UHJB

Type: 30A MaxiFuse

Feeds: Circuit 302

If one of the following circuits is operating normally, the fuse is most likely good:

    • Power windows
    • Rear wiper

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 ground splice packs).

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 ground 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

Check for OPENS/SHORTS

Repair as needed.

Components

Widow 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.

Wiper Motor

Check the circuits, connectors, and terminals that are attached to the wiper motor.

Check for OPENS/SHORTS

Wiper module should not be tested out of vehicle, it must be connected to the wiper switch to work properly. The internal control module and motor are serviced as one unit and should not be taken apart.

Repair is by replacement only.

If a new rear wiper motor is installed and the complaint is fixed, install the old motor to verify the problem was in the motor. If the complaint does not appear again, check the terminals and connections for damage, corrosion, and terminal tightness.

Rear Washer Pump

Check the circuits, connectors, and terminals that are attached to the washer module.

Check for OPENS/SHORTS

Disconnect rear washer pump and connect DVOM between the 2 terminals, 1 and 2, of the harness connector. With the ignition in RUN, activate the rear washer switch.

    • If battery voltage is measured, all of the circuits and the switch are OK. Replace the rear washer pump.
    • If the battery voltage is not measured, check the circuits and switch for OPENS/SHORTS.

Repair and replace as needed.

If a new pump is installed and the complaint is fixed, install the old pump to verify the problem was in the pump. If the complaint does not appear again, check the terminals and connections for damage, corrosion, and terminal tightness.