K 2500 Truck 4WD V8-305 5.0L (1985)
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Wiper Motor: Testing and Inspection
Two Speed Round Motor
On models with pulse wipers, refer to ``Multiplex Wiper System'' for testing procedures.
Fig. 7 Gearbox relay & drive gear assembly. Shown in park position
Fig. 14 Connections to operate round wiper motor independent of vehicle wiring
WIPER INOPERATIVE
1.
Remove washer pump to gain access to relay switch assembly.
2.
Connect 12 volt source to wiper, feed side to center terminal, ground side to gear housing, Fig. 14. Do not connect jumper to terminal 1 and 3.
3.
To determine if relay coil is open, connect test lamp to wiper terminal No. 1. Test lamp should light.
4.
Test relay switch as follows:
a. If gear mechanism is in full park position insert a small screwdriver into the switch slot (between the drive pawl and the relay latch arm) and
push relay latch arm downward and toward the relay coil in direction of the arrow, Fig. 7. Next, remove a small amount of insulation from
black lead with pink tracer and touch test lamp to exposed wire.
b. If test lamp lights but motor doesn't run, motor is defective.
c. If test lamp doesn't light, relay switch is defective. Cover exposed wire with tape after the test.