Symptom Related Diagnostic Procedures

WIPER FAILS TO OPERATE
1. Binding linkage.
2. Faulty instrument panel switch.
3. Linkage disconnected.
4. Faulty motor.
5. Open or grounded wiring.
6. Motor not grounded.
7. Faulty circuit breaker.
8. Shorted park switch.
9. Jammed or faulty gear box mechanism.
10. Motor overheated.
MOTOR RUNS BUT OUTPUT CRANK DOES NOT TURN
1. Stripped intermediate gear.
2. Stripped output gear.
3. Output gear slips on output shaft.
4. Crank not fastened properly to output gear shaft.
5. Broken latch slips on output shaft.
MOTOR DRAWS EXCESSIVE CURRENT
1. Shorted or burned armature.
2. Seized armature bearing.
3. Bearings loose in housing.
4. Loose or chipped magnets and loose clips or chips interfering with armature.
5. Broken brush holder.
6. Binding linkage.
7. Jammed gear box mechanism.
NO SPEED CONTROL (MOTOR RUNS AT ONE SPEED ONLY)
1. Open circuit in red or brown wiring.
2. Defective control switch.
3. Brush sticking in holder.
4. No brush spring.
5. Broken brush holder.
6. Low speed torque limiting resistor open.
MOTOR WILL NOT STOP WHEN INSTRUMENT PANEL SWITCH IS TURNED "OFF"
1. Broken island on gear.
2. Motor housing not grounded (two speed with concealed wipers).
3. Defective armature brake switch.
4. Broken brush holder.
5. Defective motor park switch.
MOTOR STOPS IN ANY POSITION WHEN INSTRUMENT PANEL SWITCH IS TURNED "OFF"
1. Motor park switch failure.
2. Open parking circuit.
3. Open field circuit.
WIPER BLADED NOT PARKING PROPERLY
1. Arm set at incorrect position.
2. Motor park switch timing incorrect.
3. Loose clutch spring on crank (two speed concealed).
BLADES STOP AGAINST WINDSHIELD MOULDINGS
1. Improperly adjusted wiper arm.
2. Looseness of the motor crank or other drive parts.
BLADES CHATTER
1. Twisted arm holds blade at wrong angle to glass.
2. Bent or damaged blades.
3. Foreign substances such as body polish on glass.