O.K.? What's the secret about wiper motors?

[SBPage1]

I have a 1988 C3500 w/7.4. Been having the same issues with wipers working sporadically. Went to local parts store and bought some Dielectric Grease and some Contact cleaner. Took module out, cleaned the contacts on both ends of module, put dielectric grease on contacts at both ends, as well as running a piece of sandpaper across the contacts that look like points. Reinstalled module and it works like a champ!

Antiquated system for sure. Give the cleaner and gel a try!