Debugging Intermittent Wiper Problem

[Selah94]

Hello Everyone:

I discovered a little trick today when debugging my problem. Last week my truck's Lo and intermittent wipers would no longer work. They would only work on the Hi setting. So, I looked into my Haynes Manual and found the gray wire into the wiring harness on the wiper motor carried the voltage for the Lo and intermittent wipers from the turn signal switch. So, I attached a volt meter and began reading the voltage coming down the gray wire when the wiper was on Lo and found it to be right around 12 volts. As I progressed down from Lo to the lowest Intermittent wiper setting, I noticed the voltage progressively dropped to around 10 volt at the end. This proved to me that switch in the turn signal was working correctly. Nice to know and I have heard the signal arm switch cost a bundle of money.

When I then opened up the control module on the top-right of the wiper motor, I found there was a black cylindrical thing laying in the housing. I talked to my Dad (who knows a lot more about eletronics than me) and found out this was a capacitor. I was able to solder the capacitor back onto the circuit board and everything worked great! (another side note, make sure the silver band on one end of the capacitor is on the same side as a line and arrow on the circuit board, I first installed it backwards and then had to take it out and flip it around).

Hope this little note helps someone out there in Internet land. I have found these forums a lot of help, so I figured I would try to help someone in turn.

Good night!