Symptom Related Diagnostic Procedures
Fig. 5 Compound wound round winshield wiper motor w/multiplex pulse system:
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, repair or replace wiper motor.
d. If fuses continue to blow with harness disconnected, or if fuse was satisfactory (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, gearbox relay 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 in timer connector and terminal 2 in gear box 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, remove washer pump and reconnect electrical connectors to wiper motor.
10. With wiper switch in low position, check for battery voltage at red wire to pulse relay, using a test lamp.
11. If lamp fails to light, replace gear box relay. If lamp lights, connect test lamp between pulse relay yellow wire and ground.
12. If wipers operate, replace pulse timer assembly. If wipers do not operate, check for battery voltage at pink/black wire to pulse relay, using test lamp.
13. If lamp fails to light, replace pulse relay. If lamp lights, repair or replace wiper motor.
Fig. 5 Compound wound round winshield wiper motor w/multiplex pulse system:
Fig. 15 Gear box relay & drive gear assembly inspection:
Fig. 18 Ratchet wheel and override switch assembly:
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 gear box 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 gear box relay latch arm spring, Fig. 15. If spring is properly installed, replace gear box relay.
3. If wipers do not operate properly in delay position, proceed as follows:
a. Place wiper switch in off position, then turn ignition off and on.
b. If wipers park properly, check condition and adjustment of holding switch, and repair as needed.
c. If holding switch is satisfactory, replace pulse timer assembly.
d. If wipers stop but do not park properly after performing step a., inspect override switch contacts, Fig. 18.
e. If switch contacts are held open by ratchet wheel, check for grounded blue wire and repair as needed.
f. If override switch contacts are not held open, check for loose or defective pulse timer or improperly adjusted override switch.
Fig. 15 Gear box relay & drive gear assembly inspection:
Wipers Cycle In & Out Of Park Position
1. If wipers operate properly at low speed, check drive pawl and spring and gear box relay latch arm spring, Fig. 15.
2. If drive pawl and latch arm springs are satisfactory, replace gear box relay.
3. If motor does not operate properly at low speed, refer to ``Motor Operates At High Speed Only.''
Fig. 5 Compound wound round winshield wiper motor w/multiplex pulse system:
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 gear box 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, repair or replace motor.
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 gear box 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, repair or replace motor.
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, replace pulse timer. If meter indicates no continuity, replace wiper switch.
Fig. 5 Compound wound round winshield wiper motor w/multiplex pulse system:
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, remove washer pump cover and reconnect all electrical connectors to motor.
5. With wipers operating and switch in mid-delay position, disconnect lead between pulse timer and pulse relay.
6. If wipers stop, replace pulse timer assembly. If wipers do not stop, replace pulse relay.
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, replace circuit breaker and brush plate assembly.
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, repair or replace motor.