Operation CHARM: Car repair manuals for everyone.

Multiplex Wiper System

Fig. 5 Multiplex pulse windshield wiper motor:





WIPERS INOPERATIVE
1. Turn ignition on and check for battery voltage at wiper motor terminal 2, Fig. 5, using a test lamp.
2. If lamp fails to light, proceed as follows:
a. Check wiper system fuse and replace if needed.
b. If fuse blows again, disconnect electrical connector to motor and replace fuse.
c. If fuse does not blow with harness disconnected, replace wiper motor.
d. If fuses continue to blow with harness disconnected, or if fuse was satisfactory in step ``a,'' repair feed circuit to wiper motor.
3. If lamp lights in step 1, check for battery voltage at motor terminal 1.
4. If lamp fails to light, check terminal board connections and repair as needed. If connections are satisfactory, motor is defective.
5. Place wiper switch in low position, disconnect electrical connector to gear box relay and connect test lamp between terminals 1 and 2 in connector.
6. If lamp fails to light, check continuity of wiring between motor and switch, switch continuity and ground, and repair as needed.
7. If lamp lights in step 5, place wiper switch in high position, disconnect electrical connector to pulse timer and connect test lamp between terminal 6 and timer connector and terminal 2 in gearbox relay connector.
8. If lamp fails to light, check continuity of wiring between motor and switch, switch continuity, and repair as needed.
9. If lamp lights in step 7, motor is defective.


Fig. 15 Gearbox relay & drive gear assembly inspection:





WIPERS WILL NOT SHUT OFF
Crank Arm Rotates 360°
1. Operate wipers with switch in delay position.
2. If wipers operate properly in delay position, proceed as follows:
a. Place wiper switch in off position, disconnect electrical connector to gearbox relay, and connect test lamp between terminals 1 and 2 in connector, Fig. 5.
b. If lamp lights, check for grounded wire between motor and switch or defective switch, and repair as needed.
c. If lamp does not light, remove washer pump and inspect gearbox relay latch arm spring, Fig. 15. If spring is properly installed, motor is defective.
3. If wipers do not operate properly in delay position, motor is defective.



Wipers Cycle In & Out Of Park Position
1. If wipers operate properly at low speed, motor is defective.
2. If motor does not operate properly at low speed, refer to ``Motor Operates At High Speed Only.''


Fig. 5 Multiplex pulse windshield wiper motor:





MOTOR OPERATES AT HIGH SPEED ONLY
1. Ensure electrical connector to gear box relay is secure, turn ignition on, and place wiper switch in low position.
2. Connect jumper wire between terminal 3 on gearbox relay, Fig. 5, and ground, leaving harness connected.
3. If motor operates properly at low speed, check continuity between wiper motor and switch, switch continuity and ground, and repair as needed.
4. If motor does not operate at low speed with terminal 3 grounded, motor is defective.

MOTOR OPERATES AT LOW SPEED ONLY (OPERATES PROPERLY IN DELAY & PARKS PROPERLY)
1. With ignition on and wiper switch in high position, disconnect electrical connector to gearbox relay, Fig. 5, and connect test lamp between terminals 2 and 3 in connector.
2. If lamp fails to light, check continuity of wiring between motor and switch, switch continuity and ground, and repair as needed.
3. If lamp lights, motor is defective.



MOTOR INOPERATIVE IN DELAY MODE
1. Place wiper switch in mid-delay position and disconnect electrical connector to pulse timer at wiper motor.
2. Connect ohmmeter between pulse timer terminal on motor and ground.
3. If meter indicates continuity, motor is defective. If meter indicates no continuity, replace wiper switch.


Fig. 5 Multiplex pulse windshield wiper motor:





WIPERS RUN CONTINUOUSLY IN DELAY MODE
1. Operate wipers in all switch positions. If motor fails to operate at low or high speeds, or if wipers do not park properly, correct these problems before proceeding.
2. With ignition on, place wiper switch in mid delay position and disconnect electrical connector from pulse timer at wiper motor, Fig. 5.
3. If wipers stop, check for grounded wire between pulse timer and wiper switch. If wiring is satisfactory, replace wiper switch.
4. If wipers do not stop when timer is disconnected, motor is defective.



INTERMITTENT OPERATION--BLADES STOP RANDOMLY DURING OPERATION
1. Remove wiper system fuse and connect ammeter across fuse terminals.
2. Operate wipers at low speed while observing current draw on meter. Readings will fluctuate.
3. If lowest reading is 5---6.5 amps, motor is defective.
4. If lowest reading exceeds 6.5 amps, replace wiper blades and repeat test.
5. If lowest reading still exceeds 6.5 amps, disconnect linkage from motor and repeat test.
6. If current draw is less than 6.5 amps, repair binding linkage. If current draw exceeds 6.5 amps, motor is defective.