In the distant past, windshield wiper operation had only 2 purposes: on and off. Over time, car manufacturers introduced low, medium and high speeds, and eventually added intermittent wiper functionality. These series of developments provided drivers with a wider range of speeds for varying levels of precipitation.
This functionality depends on a component called a relay – the same technology that powers your fuel pump and keeps your car’s computer running. The relay uses electrical resistance relative to the position set on the wiper control arm to determine the specific speed at which the wipers move.
Because the intermittent wiper relay is electronic, it will unavoidably fail and need replacement.
Facts to Note:
Intermittent wiper relay inspection is not part of most upkeep services.
Without the relay, your wipers will still work, but they will not offer variable speeds.
How to Fix:
The intermittent wiper relay is confirmed it needs replacement
The defective intermittent wiper relay is removed
The new intermittent wiper relay is fixed
The intermittent wiper relay is energized to turn it on
The wipers are tested to work properly in all control positions
Intermittent wiper operation isn’t compulsory to drive your vehicle, and as long as your windshield wipers work, you’re legally permitted to drive while raining. However, lack of such an option can be a major inconvenience. If your wipers no longer work on the intermittent setting, a failed relay is likely the cause. Have it inspected by one of your expert mechanics and changed if necessary.
Common symptoms indicating you may need to change the Intermittent Wiper Relay:
Intermittent speed setting does not always work
Intermittent setting does not work at all
Importance of this service:
Working wipers are required for safety on the road, but intermittent functionality is a convenience feature. However, it can be annoying to constantly turn the wipers on and off to meet different rates of precipitation. Have the intermittent wiper relay changed when it’s practical to do so.