Delay Wiper Module

Scott91370 said:

I can't even find one on ebay - not sure I'd pay $175 even if I did, I'm a cheap skate. I can't believe with as many of these trucks that are still out there, nobody makes a replacement. The wipers in mine stop right where they are when you shut them off and the sprayer doesn't work. From what I understand this module controls both but an be bypassed (haven't found out how) to make the wipers work just like plain old on/off wipers. I may pull mine and open it up to see if there is anything a plain ol' Joe can do with it. If so I will take pics and do a writer up.

Click to expand...

I could be mistaken, but I'm pretty sure the wiper park positioning is a function of the wiper motor and not the module. I also don't believe the windshield washer is controlled at all by the module other than direct power pass through.

Danderson said:

I could be mistaken, but I'm pretty sure the wiper park positioning is a function of the wiper motor and not the module. I also don't believe the windshield washer is controlled at all by the module other than direct power pass through.

Click to expand...

Hmm, that makes things even worse. Or maybe better since the module can't be bought but the motor can.

Scott91370 said:

A little searching and found this. Will it help anybody? Not sure but hope so.
https://www.gmsquarebody.com/threads/wiper-pulse-module-15598496.28952/

I doubt I'll be able to do anything with it, I like electronics but don't understand them, even mid-range simplicity, very well.

Click to expand...

That thread looks be for the 1984 up module. But, thanks for the effort!

There's a NOS module on Ebay for only $655.00 !! Hope nobody buys it before me!

That is crazy!!! Good thing you didn't post the link, I may head headed there.

The NOS I saw for that money was for a 77, 78-83 are different

I purchased a refurbished wiper intermittent module from a member on here about a year ago. he had 1 or 2 more at that time.

gmachinz was his user name.

tadslc said:

I purchased a refurbished wiper intermittent module from a member on here about a year ago. he had 1 or 2 more at that time.

gmachinz was his user name.

Click to expand...

He's been banned from most of the forums for taking people's money and not delivering. I have a couple that need to be refurbished and I'm not sure what to do about that now. There was a member here who indicated is was a pretty simple refurb so I need to get some details from him. If I can get that info I'll post it here.

to add a little more information here. I had an issue only in intermittent wipers also on my 1990 suburban. I replaced the module as the likely culprit first, but the issue remained. I suspected the switch in the column next. but that also didn't fix the issue. last up was the wiper motor (with integrated park switch and circuit breaker), and that seems to have corrected the issue. I am not sure if the circuit breaker was going bad or if the park switch came out of adjustment and the delay pulse wasn't enough to get the wipers out of park mode. just throwing this out there in case it helps somebody.

Bextreme04 said:

The module only controls the wiper speed. It just passes through all the other things. The wiper switch and the module have the same plug, you just unplug the module from the switch and unplug the harness from the module and then connect the harness straight into the switch. That's on the 78-80 with the switch on the dash, 81-83 should have the column switch and the harness connections should be right there near the module, you just unplug both connections from the module and plug them together.

Click to expand...

Sourcing one of these 78-83 modules seems to have been a problem for a while. Has anyone come up with a solution? I took the cover off one of them it appears there are a few capacitors. Usually that is where the problem starts on old electronics. Not that it matters much, is the pulse function in the switch or module? I might attempt repairing one of these if I can source small electronics parts. Anyone know where to find them.

fast 99 said:

Sourcing one of these 78-83 modules seems to have been a problem for a while. Has anyone come up with a solution? I took the cover off one of them it appears there are a few capacitors. Usually that is where the problem starts on old electronics. Not that it matters much, is the pulse function in the switch or module? I might attempt repairing one of these if I can source small electronics parts. Anyone know where to find them.

Click to expand...

The pulse is in the module. The length of the delay comes from a variable resistance in the circuit from turning the knob.

Thanks, then I have 2 failed modules.

Guess it depends what the problem is with your modules. Mine had a weird problem detailed here.....

https://www.gmsquarebody.com/threads/weird-wiper-delay-video.27859/

You are correct that those old electrolytic caps are notorious for drying out or cracking and leaking electrolyte all over the board. I did replace the five electrolytic caps on the board and that fixed my problem but I have some training.
You have four axial caps and one radial cap. You need to know the voltage rating, microfarad value and then find the right axial or radial replacement.
Trying to find the right caps was a hassle unless you have access to some electronic stores with a vast stock of caps. Trying to find these stores now is even harder than trying to find a new module.
I ended up getting an assortment of radial caps from Amazon that had close enough values that I could make them work even in place of the factory axial caps. They weren't the exact values but I knew what I could substitute without issues.

Thanks for the info. Until there is a replacement sounds like this would be a good cottage industry repair.

Am a little mad at myself. Had about 20 of these modules a few years ago. Listed one or 2 on evil bay, no interest. Tossed them in the trash. Have to tell myself they were all bad.

This is another one of those things that could be easily re-popped. A friend of mine is a retired Fanuc tech - used to have NLA proprietary boards remade at a company that reversed engineered anything electronic. I sent a guy to him who rebuilt early FI (D-Jetronic, early 70s) boxes and 4-N gauge clusters. This place wanted a working example which they reverse engineered - and then were even able to mass produce if you wanted (IIRC min order was 75-100pcs). Initial cost wasn't cheap but then everything after was very reasonable. Problem will be how many would sell? Not enough to take the leap. BTDT.