Jerry, I went ahead and bought a new AC Delco delay module. I hate to just start replacing parts but with your used module, the possibility of it being bad was there. In any case, replacing the module did not help.
Hatzie, thank you for the video....he makes it look like a daunting task.
Yes Dave, I agree - I think you are doing the right thing by buying the module. You were already aware of my increasing doubt about whether the one I forwarded to you was a good spare. Everything we checked during the diagnostic procedure appeared to be okay - the module was the last component and the only wildcard. I'm guessing that those pulse modules are kind of like a Saab DIC - factory sealed and full of solid state electronics. Since the internals cannot be inspected/tested, all you can really do is test the circuits/leads that connect to them. Very few people know what goes on inside them anyway (I certainly don't). So even if you could get them open, you'd probably need the proprietary schematics - and a Masters in Electrical Engineering - to even know where to start.
After checking everything coming in and out of the module - and finding nothing wrong - all you have left as far as a diagnostic procedure is "in-line verification" (shot gun repair). Remove the suspect component, replace it with a known good unit and observe operation.
Pull the one I sent you out, plug in the new one and cross your fingers. Even if the new module cost $50 - and you do get intermittent wipers - that is money well spent. To tear the upper steering column apart and replace the switch is a thankless, tedious, lose/lose job - especially if the switch turns out not to have been the problem.
If your new module does the trick, chuck mine - or make a paper weight out of it - and pull your Paypal money back. The shipping was essentially free because I was able to stuff it in the box with the speaker.
