Wiper Motor: Testing and Inspection
Current Draw Test1. Ensure wipers are in park position.
2. Disconnect battery.
3. Remove wiper arm and blade assemblies.
4. Remove wiper module vacuum manifolds.
5. Disconnect wiper module electrical connectors.
6. Remove one nut and five screws retaining the wiper module. Remove module from vehicle
7. Remove linkage drive arm-to-motor crankpin retaining clip. Separate drive arm from crankpin.
8. Remove three wiper motor retaining screws. Remove motor.
Fig. 39 Wiper Motor Current Draw Test:
9. Make test connections as shown Fig. 39. Alternately connect the red jumper wire to high and low speed wiper motor terminals.
10. Current draw at either terminal should not exceed 3.5 amps. Replace or repair as needed.
11. Install wiper motor. Ensure wiper motor is in the park position.
12. Install linkage drive arm to motor crankpin. Install retaining clip.
13. Install wiper module.
14. Connect wiper module electrical connectors.
15. Install wiper module vacuum manifolds.
16. Install wiper arm and blade assemblies.
17. Reconnect battery.
Park Operation Test
Refer to SCHEMATIC DIAGRAMS/ELECTRICAL AND ELECTRONIC DIAGRAMS when performing the following test procedures.
1. Turn ignition switch to ON.
2. Turn wiper switch to LO. Ensure wiper operation is proper.
3. With wipers in a vertical position turn wiper switch to OFF. Ensure wipers cycle once then park below the windshield.
4. If wipers do not function as described, perform test steps 5 through 10 according to wiper malfunction.
5. If wipers stop without cycling and parking proceed as follows:
a. Disconnect wiper motor park switch electrical connector.
b. With ignition switch ON, check for battery voltage at park switch electrical connector (red wire) terminal 63. If battery voltage is not present repair the circuit.
c. If battery voltage is present at terminal 63, check motor housing ground. Repair as needed.
d. If motor housing ground is good, turn ignition switch to OFF, then disconnect wiper motor electrical connectors.
e. Using a suitable ohmmeter, check for continuity between wiring harness terminals 28 and 58. If continuity does not exist, repair the open circuit.
f. If continuity does exist between terminals 28 and 56, check for ground at wiper motor terminal 28. If ground is open, replace wiper motor.
g. If ground is good at wiper motor terminal 28, check for continuity between wiring harness circuits G2 and 63. If continuity does not exist, repair the open circuit. If open circuit is traced to interval governor, check for continuity between wiper switch terminals P and G. If open exists between terminals P and G, replace the wiper switch.
h. If open does not exist between wiper switch terminals P and G, replace the interval governor.
6. If wipers travel into the next cycle, then park on the windshield, proceed as follows:
a. Perform wiper switch continuity test as described under WIPER SWITCH.
b. On non-intermittent systems, if wiper switch continuity test is good, replace wiper motor.
c. On intermittent systems, if wiper switch continuity test is good, check for voltage at washer terminal 941. If voltage is present repair as needed.
d. If voltage is not present at washer terminal 941, disconnect wiper motor electrical connectors and proceed to next step.
e. Check for continuity between terminals G2 and 63. If open exists, replace governor.
f. If continuity exist between terminals G2 and 63, replace wiper motor.
7. If wipers run constantly in OFF or INT positions, perform test procedures in step 6.