View Full Version : 85 GMC wiper issue..
WILMASBOYL78
10-26-2016, 09:30 PM
We have a 1985 GMC Sierra Classic 1500...bought it new. <<GRAEMLIN_URL>>/biggthumpup.gif
Last week I noticed the washers weren't squirting...just figured it was low on fluid...not the case. Also noticed that the wipers will not stop when you turn the switch to off...they keep going. If I turn the stick back for a moment to the manual spot and let it go...they will stop. <<GRAEMLIN_URL>>/rolleyes.gif
So, I am considering connecting 12v to the washer pump motor to see if it works...the other issue has me stumped. By the way, the wipers appear to have the same speed regardless of where the knob is set...speed doesn't change. <<GRAEMLIN_URL>>/hmmm.gif
Any thoughts would be appreciated.
-wilma
PeteLeathersac
10-26-2016, 10:19 PM
'
Is '85 first year for the separate pump @ the tank?
Unless wiper trans/pivots seizing, it's often the motor itself.
Here's an '87 trouble tree you can try...
http://www.chevyk5blazer.com/forums/show...th-Stalk-wipers (http://www.chevyk5blazer.com/forums/showthread.php?4192-87-Wiper-troubleshooting-Any-year-with-Stalk-wipers)
Good luck!
<<GRAEMLIN_URL>>/beers.gif
~ Pete
WILMASBOYL78
10-27-2016, 11:33 AM
The pump is mounted into the back of the tank.
Thank for the tech help...hopefully we can figure it out.
-wilma
earntaz
10-27-2016, 01:18 PM
Don't forget to check the grounding circuit first ... TAZ
njsteve
10-27-2016, 02:11 PM
There was a recall on wiper motors in the mid 1990s. I know my 1995 Suburban was part of it. I don't know the date range for affected trucks. It had to do with water getting into the circuit board and causing all sorts of gremlins in the wiper system.
68l30
10-27-2016, 04:14 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: njsteve</div><div class="ubbcode-body">There was a recall on wiper motors in the mid 1990s. I know my 1995 Suburban was part of it. I don't know the date range for affected trucks. It had to do with water getting into the circuit board and causing all sorts of gremlins in the wiper system. </div></div>
^^^ What Steve said! My 94 did the same thing, drove me nutz. It had a mind of it's own.
BIG
WILMASBOYL78
10-27-2016, 04:21 PM
I heard about the circuit board issues...pretty sure the 85 is <span style="font-style: italic">pre-circuit board tech</span>...according to boys at NAPA.
Charley Lillard
10-27-2016, 06:35 PM
Early wiper issues are usually grounding related like Taz mentioned.
WILMASBOYL78
10-27-2016, 07:24 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Charley Lillard</div><div class="ubbcode-body">Early wiper issues are usually grounding related like Taz mentioned. </div></div>
OK...since anything beyond a D cell battery is over my head <<GRAEMLIN_URL>>/rolleyes.gif ...how do I check the grounding circuit you folks have mentioned. <<GRAEMLIN_URL>>/hmmm.gif
-wilma
WILMASBOYL78
10-28-2016, 06:00 PM
I'm going to work on the truck over the weekend...how do I properly test the ground circuit??
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WILMASBOYL78</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Charley Lillard</div><div class="ubbcode-body">Early wiper issues are usually grounding related like Taz mentioned. </div></div>
OK...since anything beyond a D cell battery is over my head <<GRAEMLIN_URL>>/rolleyes.gif ...how do I check the grounding circuit you folks have mentioned. <<GRAEMLIN_URL>>/hmmm.gif
-wilma </div></div>
HawkX66
10-28-2016, 06:18 PM
The simplest way to see if it's a ground issue is to run a separate ground. You could run a separate wire from a known good ground contact directly to the wiper case/ground wire. If when you turn the wipers on they aren't working, then you hook up the ground and they work, you'll know it's the ground. From there, you just find where the ground circuit has been broken. Broken wire, loose screw, rusted ground contact etc...
WILMASBOYL78
10-28-2016, 06:27 PM
thanks...almost too simple <<GRAEMLIN_URL>>/rolleyes.gif
HawkX66
10-28-2016, 07:08 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WILMASBOYL78</div><div class="ubbcode-body">thanks...almost too simple <<GRAEMLIN_URL>>/rolleyes.gif </div></div>
That's what four years of Electronics in school gets you. <<GRAEMLIN_URL>>/wink.gif
WILMASBOYL78
10-28-2016, 07:34 PM
The most technical electrical thing for me is using a 2 prong adapter on a 3 prong cord <<GRAEMLIN_URL>>/hmmm.gif
Not sure how to check it....but I would bet it is a bad ground inside the motor
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