Operation CHARM: Car repair manuals for everyone.

Modified Pulse Wiper System

Fig. 4 Modified pulse windshield wiper motor:





Wiper Inoperative
1. Connect a test lamp to wiper terminal No. 2, Fig. 4, and turn ignition ``On.'' If test lamp does not light, check for blown wiper fuse. If fuse is satisfactory, check for an open circuit between wiper terminal No. 2 and fuse block.
2. If fuse is blown in Step 1, disconnect wiring connector from wiper terminals 1, 2, 3, replace fuse and turn ignition ``On.'' If fuse blows, check for a grounded circuit between wiper terminal No. 2 and fuse block.
3. If fuse does not blow in Step 2, reconnect wiring connector to wiper terminals and, with ignition ``On,'' place dash switch in ``Lo'' position. If fuse blows, motor is defective.
4. If test lamp lights in Step 1, connect a test lamp between black wire with pink stripe and the ground. Place dash switch in ``Lo'' position and turn ignition ``On.'' If test lamp lights, motor is defective.
5. If test lamp remains off in Step 4, connect a jumper wire between wiper terminal No. 1 and ground. Place dash switch in ``Lo'' and turn ignition ``On.'' If wiper operates, check for open circuit between wiper terminal No. 1 and dash switch, an improperly grounded dash switch or a defective dash switch.
6. If wiper remains inoperative in Step 5, motor is defective.

Wiper Inoperative In Delay
1. Disconnect wiring connector from wiper terminals Nos. 6 and 7, then connect a voltmeter between connector terminal No. 7 and ground, Fig. 4. Place dash switch in ``Mid'' delay and turn ignition ``On.'' If voltmeter indicates 12 volts, motor is defective.
2. If voltmeter reading in Step 1 is zero volts, check B+ circuit to dash switch, wiring between dash switch and wiper and to ensure dash switch is satisfactory.

Wiper Will Not Pulse (Runs Continuously in Delay Mode)
1. Disconnect wiring connector from wiper terminals Nos. 6 and 7, remove lead from connector that connects to wiper terminal No. 6, Fig. 4, then reinstall connector. Place dash switch in ``Mid'' delay and turn ignition ``On.'' If wiper operates properly, check for: grounded circuit between wiper terminal No. 6 and dash switch or a defective dash switch.
2. If wiper runs continuously in Step 1, motor is defective.


Fig. 17 Ratchet wheel & override switch assembly:





Wiper Will Not Shut Off
1. Disconnect wiring connector from wiper terminals Nos. 1, 2, 3, then remove lead that connects to wiper terminal No. 1, then reinstall connector. Place dash switch in ``Off,'' and turn ignition ``On.'' If wiper shuts ``Off,'' check for a grounded circuit between wiper terminal No. 1 and dash switch.
2. If wiper continues to run in Step 1, remove washer pump cover and reconnect all disconnected wiring. Disconnect green lead from wiper terminal 1, place dash switch in ``Off'' and turn ignition ``On.'' If wiper continues to run, motor is defective.
3. If wiper shuts ``Off'' in Step 2, check if ratchet gear is opening override switch contacts, Fig. 17. If gear is correctly positioned and the switch contacts are open, check the disconnected green leads for grounds.
4. If ratchet gear is properly positioned and the switch contacts are closed, torque mounting screw to 14 inch lbs., and adjust contact gap to .025 inch.


Fig. 18 Washer relay armature leg position 1:




Fig. 19 Washer relay armature leg position 2:





Wiper Will Not Shut Off & Washer Runs Continuously
1. Remove washer pump cover and reconnect wiring. Place dash switch ``Off'' and turn ignition ``On.'' Check position of washer relay armature leg with unit operating. If relay armature is in No. 1 position, Fig. 18, check that Binding park switch actuator or defective park switch ratchet gear dog spring engages gear teeth. Tighten mounting screw or replace as required.
2. If relay armature leg is in No. 2 position, Fig. 19, push button and check if relay armature leg drops on armature leg ramp and pump completes wash cycle and wiper shuts ``Off'' in position 1. If relay armature leg drops back into slot, motor is defective.
3. If relay armature leg drops on ramp, pump completes cycle and wiper shuts ``Off'' in Step 2, check for loose coil on pole piece or a missing relay armature. If a burr is present on end of armature leg, file off burr and recheck unit.



Wiper Will Not Shut Off--Blades Move In & Out of Park
1. With ignition ``On,'' check wiper operation in ``Lo'' and ``Hi'' speeds. If wiper operates in both speeds, motor is defective Wiper will not delay if operates only in ``Hi'' speed.
2. If wiper operates in ``Hi'' speed only in Step 1, connect a jumper wire between wiper terminal No. 3 and the ground. Place dash switch in ``Lo'' and turn ignition ``On.'' If wiper still has ``Hi'' speed only, motor is defective.
3. If wiper has ``Lo'' speed in Step 2, check for an open circuit between wiper terminal No. 3 and dash switch or a defective dash switch.

Wiper Has Hi Speed Only
1. Connect a jumper wire between wiper terminal No. 3 and the ground. Place dash switch in ``Lo'' and turn ignition ``On.'' If wiper still has ``Hi'' speed only, motor is defective.
2. If wiper has ``Lo'' speed in Step 1, check for open circuit between wiper terminal No. 3 and dash switch or a defective dash switch.

Wiper Has Lo Speed Only
1. Disconnect wiring connector from terminals 1, 2, and 3 and remove lead that connects to wiper terminal No. 3, then re-install connector. Place dash switch in ``Hi'' and turn ignition ``On.'' If wiper still has ``Lo'' speed only, motor is defective.
2. If wiper has ``Hi'' speed in Step 1, check for grounded circuit between wiper terminal No. 3 and dash switch or a defective dash switch.

Wiper Operates Intermittently
1. Remove wiper system fuse from fuse block and connect an ammeter across fuse block terminals. Place dash switch in ``Lo'' and turn ignition ``On.'' Operate motor and after two minutes of operation, observe ammeter for lowest current reading. If lowest current reading was 5---6.5 amps, motor is defective.
2. If lowest current reading exceeds 6.5 amps, replace wiper blade elements and repeat Step 1. If current draw is less than 6.5 amps, condition is corrected.
3. If lowest current reading in Step 2 still exceeds 6.5 amps, disconnect wiper linkage from crank arm and repeat check. If current draw is below 6.5 amps, check for binding wiper linkage. If current draw still exceeds 6.5 amps, motor is defective.