I had the same issue with my 1995 Tahoe. I replaced the turn signal / wiper indicator (left of the steering column), but it did not fix the problem. This was also a major PITA.
I then changed out the wiper electronic board under the hood. This is mounted near the wiper motor against the firewall. Black case approx 4" X 6". You will need a torq or allen wrench to take the cover off.
10 minute fix. The part was available from O reileys for +/- $20.
Saturday, February 7th, 2009 AT 11:13 PM