Pulse wiper question


Buick Newbie
Buick Ownership
Having an issue with my wipers. With the engine off key on condition, the wipers work properly. With the engine running, the wipers only have low and high speed and will not shut off. In order for the wipers to "park" i need to turn the engine off, and recycle the key to the "on" position. Spraying the washer fluid turns the wipers on, but again they will not park and continue to run until the key is switched off.

While the wipers were running i unplugged the switch, which yielded no change. I wiggled the wire harness to the motor and no change.

From what i understand GM uses a "wiper pulse board" to control the wiper timing and park. Looking at it, i cant see anything wrong with it. Went to the local "You-Pull-It" and grabbed another one ($10) just to try but again, no change. Can't find anywhere that has a new replacement that fits this thing, and most parts store clerks look at me like a have 2 heads when i ask them. No local so called "electronic repair" store is willing to look at it (but they'll plug in a new screen on your smart phone!).

Also tried a new wiper motor (didn't think it would do anything but didnt want to leave the parts stores with nothing...) Not surprised no change, but remarkably quieter so happy with that result.

Am i missing something? Is there a possibility its an issue with the switch on the column? Any pinpoint tests for this. The ignition position is throwing me off, why does the engine running affect the wipers? Anyone know of anywhere to get a NOS Pulse Board or somewhere that refurbishes/tests them? Its really annoying in Florida where we have random sun showers to be sitting in traffic with the wipers going full bore after a brief shower, and having to pull over and restart the car to shut them off. Thanks.


Full Member
Buick Ownership
2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
There are GM Pulse Boards listed on Amazon and Dorman may have them, but if any will work for you that's something you will need to check.

There's also pulse board repair instructions, videos and sites, they be useful to check out.