Mechanics

GMC SUBURBAN STEERING PROBLEM

1990 GMC Suburban • 168,000 miles

I am trying to determine (trouble shoot) a wiper problem so that I dont have to start replacing parts hoping to get the right one first. I no longer have window wash- I have removed wash motor and checked and it works fine. I no longer have intermittent wipe, and only one speed in stead of having High-Low speeds. Is the problem in the wiper motor itself or is it the switch in the column. Thanks
Avatar
James3154
October 26, 2012.




Start by checking the pulse module at left side of steering column-this is the heart of the wiper/washer system other than the switch


Tiny
Rasmataz
Oct 27, 2012.
Hello, ok thanks but I was wanting to print the schematic since I cant see what goes where. Anyway to email those drawings to me, Is the pulse module on the steering column itself or is this what you are calling the column switch part. I guess I don't understand your answer.


Tiny
James3154
Oct 29, 2012.
Please correct me if I am wrong, doesn't my wiper motor on the firewall have the pulse control module on it, Or is the module on the steering column? The wiper motor it has two places that wires plug into it. So might the module be there? If so is their a way with a OHM meter to check first the wiring from the switch on the column and the switch itself to the wiper motor/module unit on the firewall?
I really have no idea, just basing these questions on ON'line research I have done.

Thanks Kindly
James


Tiny
James3154
Oct 29, 2012.
No, its not on the wiper motor -The PWCM Its On bottom of steering column as indicated in the pic-How good are you in electrical not that swift leave it to an experienced person you might end up making things worst then it is-

Give me ur email addy-
AD


Tiny
Rasmataz
Oct 30, 2012.
I have been doing repair work on vehicles now for going on 25 years, the basics of the system are a no brainer in order to not just start replacing parts like most mechanics --ie YOU -- I will find out just how to OHM out the parts. Most if not all mechanics will start replacing parts wishing/hoping to fix the problem. Good for parts store, not to good for owner. Thanks for your time.


Tiny
James3154
Oct 30, 2012.
This module controls everything on the wiper/washer system-


Tiny
Rasmataz
Oct 30, 2012.
Thank you, I found the module, nothing more than removing the lower panel, I have ordered a new one since none of the local parts stores have one. A mechanic friend of mine also pointed me in the same direction-this module. Hopefully when the new one comes it will resolve the problem,

again thanks for your time

kindly james


Tiny
James3154
Oct 30, 2012.
Well the new part finally arrived. I removed and replaced with the new one. Well the washer motor works fine when asked to at the switch, but the wipers will not turn off, they run constantly until the key is turned off. I put the old module back in and realized that with the wipers turned on and the washer motor wired that I had delayed wiper mode. If I unplug the washer motor I dont have delayed wiper. What should I do now?
Thanks


Tiny
James3154
Nov 8, 2012.
Start testing the switches and wiring to and from the module


Tiny
Rasmataz
Nov 8, 2012.
Well lets see. Replace the module this is the key to the wiper, wash pulse -- now check the switches --
LET ME EXPLAIN A LITTLE BETTER TO YOU !
1. Had no wash (thought possibly) could be the switch but actually couldn't trouble shoot. - Removed wash motor and check'd worked fine on benchtest -- (took your advise) ordered module *********$100.00
2. Replaced module now wash works fine ___ so this tells me that the column switch if good but wipers wont turn off.
3. Re installed old module - again no wash - but all other functions good - delayed wipe so on,
4. Could this be the wiper motor itself (only) problem is no wash.

Have determined that the pulse wipe goes through the wash pump - if I disconnect the wash pump I have no delayed wipe, could bench testing the pump actually not tell me if this unit is functioning properly?


Tiny
James3154
Nov 8, 2012.

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