Wiper/washer System Chevrolet Cab & Chassis K3500

FRONT SYSTEM

System uses a permanent magnet, 2-speed, positive-park wiper motor. Motor drives a crank arm, which is attached to individual transmission links for left and right wipers. Wiper motor is sealed and not serviceable (except for delay module on pulse system). Washer pump motor is mounted on fluid reservoir.

System is either a base system or pulse (delay) system. Base system has high and low speeds. Pulse system is similar to base system, but with the addition of a delay function that causes the wipers to sweep once with a delay interval between sweeps. Variable resistor in wiper switch adjusts amount of current to a delay module attached to wiper motor. Delay module controls current to wiper motor.

REAR SYSTEM

System has a two-speed, permanent magnet, depressed park motor, with a pulse (delay) feature that causes the wipers to sweep once with a delay interval between sweeps. Variable resistor in wiper switch adjusts amount of current to delay module in wiper motor. Delay module controls current to wiper motor. Wiper motor (including delay module) is sealed and not serviceable.

SYSTEM TESTS

Note. Ensure FRONT WIPER fuse is okay before testing system. Front wiper switch connector is located near base of steering column.

Wipers Inoperative In All Modes

1. Disconnect wiper switch connector. Connect test light between ground and White wire terminal of wiper switch connector. see scheme 2 If test light does not come on, repair open in White wire between wiper switch and fuse block.
2. If test light comes on, reconnect wiper switch connector. Move wiper switch to LO position. Connect test light between ground and Gray wire terminal of wiper switch connector. If test light does not come on, replace wiper switch. If test light comes on, repair open in Gray wire between wiper switch and wiper motor.

Wipers Run At Low Speed Only

1. Disconnect wiper motor connector. Turn ignition to ACC position and wiper switch to HI position. Connect test light between ground and Purple wire terminal of wiper motor connector. see scheme 2 If test light comes on, replace wiper motor (replace delay module on pulse system).
2. If test light does not come on, connect test light between ground and Purple wire terminal of wiper switch connector. If test light does not come on, replace wiper switch. If test light comes on, repair open in Purple wire between wiper switch and wiper motor.

Wipers Run At High Speed Only

1. Disconnect wiper motor connector. Turn ignition to ACC position and wiper switch to LO position. Connect test light between ground and Gray wire terminal of wiper motor connector. see scheme 2 If test light comes on, replace wiper motor (replace delay module on pulse system).
2. If test light does not come on, connect test light between ground and Gray wire terminal of wiper switch connector. If test light does not come on, replace wiper switch. If test light comes on, repair open in Gray wire between wiper switch and wiper motor.

Wiper Motor Runs Continuously

1. Disconnect wiper motor connector. Turn ignition to ACC position and wiper switch to LO position. Connect test light between ground and Gray wire terminal of wiper motor connector. see scheme 2 If test light does not come on, repair open in Gray wire between wiper motor and wiper switch.
2. If test light comes on, move wiper switch to HI position. Connect test light between ground and Purple wire terminal of wiper motor connector. If test light does not come on, repair open in Purple wire between wiper motor and wiper switch.
3. If test light comes on, connect test light between ground and White wire terminal of wiper motor connector. If test light does not come on, repair open in White wire between ground and wiper motor. If test light glows on models without pulse wipers, go to next step. If test light glows on models with pulse wipers, replace wiper motor.
4. On models without pulse wipers, turn ignition and wiper switch off. Disconnect motor connector and measure resistance between Orange and Gray wires at connector. If resistance is zero ohms, replace wiper motor. If resistance is more than zero ohms, repair open in Orange wire between motor and switch.

No Delay In Pulse (Delay) Mode

1. Disconnect wiper switch connector. Place wiper switch in LO position. Connect ohmmeter between Gray and White wire terminals of wiper switch connector. If ohmmeter reads decidedly less than or greater than 680 ohms, replace wiper switch.
2. If ohmmeter reads about 680 ohms, move wiper switch through delay range to maximum delay position. If ohmmeter readings do not increase in steps to about 450 k/ohms, replace wiper switch. If ohmmeter readings increase in steps to about 450 k/ohms, check for open in Gray or White wire between wiper switch and wiper motor. see scheme 2 If wires are okay, replace wiper switch.

Washer Inoperative (Base System)

1. Disconnect washer pump motor connector. Turn ignition switch to ACC position and wiper switch to WASH position. Connect test light between ground and Pink wire terminal of washer pump motor connector. see scheme 2 If test light comes on, go to next step. If test light does not come on, go to step 3).
2. Connect test light between Pink and Black wire terminals of washer pump motor connector. If test light comes on, replace washer pump motor. If test light does not come on, repair open in Black wire between ground and washer pump motor.
3. Connect test light between ground and Orange wire terminal of wiper motor connector. If test light does not come on, replace wiper switch. If test light comes on, repair open in Orange wire between wiper motor and bulkhead connectors, or repair open in Pink wire between bulkhead connector and washer pump motor.

Washer Inoperative (Pulse System)

1. Disconnect washer pump motor connector. Turn ignition switch to ACC position and wiper switch to WASH position. Connect test light between ground and Pink wire terminal of washer pump motor connector. see scheme 2 If test light comes on, go to next step. If test light does not come on, go to step 3).
2. Connect test light between Pink and Black wire terminals of washer pump motor connector. If test light comes on, replace washer pump motor. If test light does not come on, repair open in Black wire between ground and washer pump motor.
3. Connect test light between ground and Gray wire terminal of wiper motor connector. If test light comes on, go to next step. If test light does not come on, check for open in Gray wire between wiper motor and wiper switch. If wire is okay, replace wiper switch.
4. Connect test light between ground and Orange wire terminal of wiper motor connector. If test light does not come on, replace delay module. If test light comes on, repair open in Orange wire between wiper motor and bulkhead connectors, or repair open in Pink wire between bulkhead connector and washer pump motor.

Note. Ensure ACC-IGN circuit breaker is okay before testing system.

Wiper Inoperative In All Modes

1. Turn ignition switch to ACC or RUN position. Connect test light between ground and White wire terminal of wiper switch connector. see scheme 3 If test light does not come on, repair open in White wire between wiper switch and fuse block.
2. If test light comes on, connect test light between ground and Gray wire terminal of wiper switch connector with wiper switch in LO position, and Light Blue wire terminal with switch in HI position. If test light does not come on at one or both wires, replace wiper switch.
3. If test light comes on at both wires, disconnect wiper motor connector. Connect test light between ground and Gray wire terminal of wiper motor connector with wiper switch in LO position, and Light Blue wire terminal with switch in HI position.
4. If test light does not come on at one or both wires, repair open in Gray or Light Blue wire between wiper motor and wiper switch. If test light comes on at both wires, connect test light from Gray or Light Blue wire terminal to Black wire terminal of wiper motor connector. Turn wiper switch to LO position.
5. If test light comes on, replace wiper motor. If test light does not come on, repair open in Black wire between wiper motor and ground.

1. Turn wiper switch to HI position. Connect test light between ground and Dark Green wire terminal of wiper switch connector. see scheme 3 If test light does not come on, replace wiper switch. If test light comes on, disconnect wiper motor connector.
2. Connect test light between ground and Light Blue wire terminal of wiper motor connector. Move wiper switch to HI position. If test light comes on, replace wiper motor. If test light does not come on, repair open in Light Blue wire between wiper motor and wiper switch.

1. Turn wiper switch to LO position. Connect test light between ground and Gray wire terminal of wiper switch connector. see scheme 3 If test light does not come on, replace wiper switch. If test light comes on, disconnect wiper motor connector. Turn wiper switch to LO position.
2. Connect test light between ground and Gray wire terminal of wiper motor connector. If test light comes on, replace wiper motor. If test light does not come on, repair open in Gray wire between wiper motor and wiper switch.

Wiper Motor Runs Continuously Or Will Not Park

1. Turn ignition switch to ACC or RUN position. Turn off wiper switch. Connect test light between ground and Gray wire terminal of wiper motor connector. see scheme 3 If test light comes on, replace wiper switch.
2. If test light does not come on, connect self-powered test light between ground and Black wire terminal of wiper motor connector. If test light comes on, replace wiper motor. If test light does not come on, repair open in Black wire between wiper motor and ground.

Washer Inoperative

1. Turn ignition switch to ACC or RUN position. Turn wiper switch to WASH position. Connect test light between ground and Dark Green wire terminal of wiper switch. see scheme 3 If test light does not come on, replace wiper switch.
2. If test light comes on, disconnect washer pump motor connector. Connect test light between ground and Dark Green wire terminal of washer pump motor connector. If test light does not come on, repair open in Dark Green wire between washer pump motor and wiper switch.
3. If test light comes on, connect test light between Dark Green and Black wire terminals of washer pump motor connector. If test light comes on, replace washer pump motor. If test light does not come on, repair open in Black wire between washer pump motor and ground.

REMOVAL & INSTALLATION

Removal & Installation (Front)

Mark park position of wiper arms with tape to aid in reinstallation. Disconnect washer hose. Lift wiper arm assembly and pull retaining latch. Remove wiper arm assembly from transmission drive shaft. To install, reverse removal procedure. Check wiper system operation.

Removal & Installation (Rear)

Disconnect washer hose. Lift wiper arm assembly and pull retaining latch. Remove wiper arm assembly from wiper motor drive shaft. Install wiper arm onto serrated wiper motor drive shaft in such a position where wiper blade will rest in a proper parked position. Lift wiper arm extension and push in retaining latch. Install washer hose. Check wiper operation.

1. Turn steering wheel to straight-ahead position. Disconnect negative battery cable. Remove instrument panel trim cover. Remove steering wheel.
2. Screw center post of Lock Plate Compressor (J-23653-SIR) onto steering shaft as far as it will go. Compress lock plate by turning center post nut clockwise. (Scheme 1)
3. Pry snap ring out of shaft groove. Discard ring. Remove lock plate compressor. Remove lock plate. Remove turn signal cancel cam. Remove upper bearing spring and thrust washer. Turn multifunction lever upward (right turn position).
4. Pull multifunction lever straight out to remove. Remove hazard warning knob. Remove turn signal switch assembly screws. Remove steering column support bracket assembly. Disconnect switch connector. Remove wiring protector covers. Pull switch assembly and wiring harness out of column.
5. To install, reverse removal procedure using NEW lock plate snap ring.

Scheme 1

Disconnect negative battery cable. Remove instrument panel bezel. Disconnect switch electrical connector. Remove switch. To install, reverse removal procedure.

WIPER MOTOR

Note. On vehicles with front pulse system, it is not necessary to remove wiper motor to remove delay module.

1. Disconnect battery negative cable. Remove wiper arms. Remove cowl vent grille. Disconnect wiper motor electrical connector. Loosen drive link bracket nuts where motor crank arm is attached to transmission arm. DO NOT remove crank arm from motor.
2. Separate transmission arm from motor crank arm. Remove wiper motor mounting screws. Remove wiper motor. To install, reverse removal procedure. Lubricate contact point of motor crank arm and transmission arm before connecting components. Tighten wiper motor mounting screws to 62 INCH lbs. (7 N.m).

Disconnect negative battery cable. Remove wiper arm. Remove motor cover. Disconnect electrical connector. Remove bolt, nut, spacer and washer from motor. Remove motor. To install, reverse removal procedure. Tighten wiper motor mounting bolt/nut to 53 INCH lbs. (6 N.m).

OVERHAUL

Repairs to wiper assembly are limited to switch, plus external parts, crank arm, spacer and plastic seal, and output shaft seal. Wiper motor is a sealed unit and can only be serviced by replacement.

See also:
• COMPUTER RELEARN PROCEDURES