ASE G1 Auto Maintenance and Light RepairElectrical/Electronic SystemsMedium
A vehicle's windshield wipers operate only on the 'HIGH' speed setting, but not on 'LOW' or 'INTERMITTENT'. The washer fluid pump also functions correctly. What is the MOST likely cause?
- AAn open circuit in the low-speed or intermittent control wiring
- BLow washer fluid level
- CA faulty wiper motor
- DA seized wiper linkage
Show answer & explanationAnswer & explanation
Correct answer: A. An open circuit in the low-speed or intermittent control wiring
If the wipers work on 'HIGH' speed, the motor itself is functional, and the power/ground for the high-speed circuit is intact. The inability to operate on 'LOW' or 'INTERMITTENT' suggests a problem with the control circuit specifically for those speeds, often an open circuit in the wiring or a fault within the multi-function switch controlling those specific modes.
Why the other options are wrong
- B. Low washer fluid level affects only the washer function, not the wiper speeds.
- C. If the wiper motor was faulty, it would likely not work on any speed, or struggle on all speeds.
- D. A seized wiper linkage would prevent movement on all speeds, not just specific ones.
Wiper Speed Control
Wiper motors often have multiple windings or control circuits for different speeds. If one speed works but others don't, the issue is typically in the specific control circuit or switch for the non-functional speeds.
- Wiper motor has multiple speed circuits.
- Different circuits for low, high, intermittent.
- Problem isolated to specific speed control.
Memory trick: Wipers: High is Fly, Low is Shy? Check the Signal Why!