Author Topic: Wiper issues  (Read 2369 times)

Offline 1967KaiserM715

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Re: Wiper issues
« Reply #30 on: October 15, 2018, 08:20:33 PM »




DID the wipers continue to run with the w/w switch OFF, ignition ON, gray & black/lt blue pair disconnected from the w/w motor?  Or did it run only when you jumpered the gray to black/lt blue?

Continued to run after turning switch off, leaving ign on, then disconnecting grey &blk/lt blu wires

If I had the ign on, and switch off (but not previously on) jumping the wires would run the motor.

I'll have to verify the test light tomorrow, I may have been in delay, not on low, if that matters. It was very dim, had there been more light (hood blocks a lot) it might not have even been noticeable.

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Current Vehicles:1985 GMC K10(Daily)
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Online bd

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Re: Wiper issues
« Reply #31 on: October 15, 2018, 08:48:25 PM »
Continued to run after turning switch off, leaving ign on, then disconnecting grey & blk/lt blu wires

The only way for this to have occurred is if the gray (ckt 91) or purple (ckt 92) wires were grounded either through the w/w switch, the delay module or arcing to chassis.
Rich
It's difficult to know just how much you don't know, until you know it....
In other words... if people learn by making mistakes, by now I should know just about everything!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline 1967KaiserM715

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Re: Wiper issues
« Reply #32 on: October 15, 2018, 09:16:25 PM »
I assume since it does it without the pulse board connected as well, it's either the switch or the truck side.

Is it possible to just run two wires from the switch connector straight to the motor to bypass the truck side? All the other wires should just be part of the pulse or washer system right? And one to ground.

 That would, in theory, narrow it down to the switch or faulty wiring on the truck side, depending on the results.  Correct?
Continued to run after turning switch off, leaving ign on, then disconnecting grey & blk/lt blu wires

The only way for this to have occurred is if the gray (ckt 91) or purple (ckt 92) wires were grounded either through the w/w switch, the delay module or arcing to chassis.

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Current Vehicles:1985 GMC K10(Daily)
1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
1991 GMC K2500(under repair)

Online bd

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Re: Wiper issues
« Reply #33 on: October 16, 2018, 12:30:01 AM »
You do have an interesting problem.  Have you been referencing the 1985 wiring manual during this process?  It will benefit you to do so if you haven't.  As long as this problem has persisted, trying a different approach seems overdue.  I think you are on the right track.

Sometimes it's prudent to establish your own "knowns" and progress from there.  Purge some confusion from the game so to speak.  You know the park switch is a problem.  Procure a wiper motor and, using jumpers and the factory wiring schematic, verify its operation on the bench before installation.  Once you know you have a fully functioning w/w motor, you can eliminate that as a variable and install it.  Next, verify all of the ground connections back to the battery negative post (i.e., wiper switch to harness to cab, cab to engine, engine to B-).  This can be accomplished rather easily with a voltage drop test.  Then establish your own circuits using jumpers directly to the switch, bypassing the delay module and factory wiring, as you suggested.  I think if you take a systematic approach, avoid assumptions and prove the circuits as you progress, you'll resolve the issue fairly efficiently.  You will need to substitute jumpers for the white (I+), black (B-), gray (low), purple (high), and black/light blue (park) wires.  Ignore the pink (washer) and brown (delay rheostat) wires.
Rich
It's difficult to know just how much you don't know, until you know it....
In other words... if people learn by making mistakes, by now I should know just about everything!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline 1967KaiserM715

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Re: Wiper issues
« Reply #34 on: October 20, 2018, 04:56:00 PM »
Well I think the truck just hates me,

First step I took was to verify a good working motor, making sure the park switch functioned. All done on the bench with a separate battery. I used a spare wiper switch, and using alligator clips, and some spare W/W motor connections, I verified the motor functioned as it should, and that that switch was good. I then took it a step farther and attached a delay module and verified all still worked as it should. Everything is looking good, I have two good motors, a good delay module, and a good switch.

Next step was a ground voltage drop test, nothing more then .5volts drop at any connection.

so from there, I then plugged in a Good Motor to the truck, and without really thinking about it, just tested it, Ign on, and using the switch and delay module(untested) already in the truck, I checked the function of the motor....Everything seemed to work as it should, mist allowed one rotation, delay worked, turning to off would park the wipers....

I'll mention that at this point everything was original as how it came on the truck, original switch, original Wiper motor(but bench tested and verified OK) and original Delay board. I am now thoroughly confused, and slightly angry that everything is working as it should, without me really changing anything. I wiggle some wires with the wipers in a delay, nothing seemed to cause any issues, off would still work, mist, etc. So I use my bench tested switch and delay module, hook those up to the truck and same thing, everything working as it should.

So Final(just kidding) step, I install the wiper motor, all connections are put together, start wipers......NO Delay, NO Mist Function, NO Off/Park. I start wiggling all the wipers, checking all the connections, I then Use the bench tested switch and delay module, same thing, no Delay, no Mist, no Park. I forget to shut off wipers and leave them in Slow Delay, walk away to grab my multi-meter and test light. By the time I get back(2 minutes tops), the wipers are stopping and then one sweep, stop, sweep, stop and so on. So as I continue to stare, they pause at the Top of the sweep....and stayed there much longer then the normal delay I was just watching. they did finally move again, but at this point there is no delay, they move in a continuous sweep, and the Off function of course isn't working.

So I use the test light an multi-meter, I'm getting full power in(12.3v) grey low speed is at 7.6v, same with high speed purple. one end of multi-meter is attached to ground. test light doesn't really tell me much.

Now, here's the interesting part, I found if I took my test light and applied light pressure to the park switch arm(the piece that rides on the gear) the motor functions as it should, applying the test light to the grey wire at the park switch did nothing, only when I applied pressure to the switch arm. Its not much pressure, and really only is applied when the arm rides up onto the cam.

So yeah, 4 hours well spent today....
Current Vehicles:1985 GMC K10(Daily)
1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
1991 GMC K2500(under repair)

Offline VileZambonie

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Re: Wiper issues
« Reply #35 on: October 21, 2018, 07:43:46 AM »
Most common problems with these wiper systems are compounded or stacked issues. High resistance especially near or at the connector for the motor, the motor itself and connections at the module are the main points of high resistance. All it takes is a little bit of resistance and pinpoint tests become a cat and mouse game. As soon as you unplug or wiggle or backprobe connections the path of least resistance changes and the mouse moves to a new place. I would recommend repairing or replacing the pigtails at the wiper motor and disassembling and cleaning the connections at the module.
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Offline 1967KaiserM715

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Re: Wiper issues
« Reply #36 on: October 21, 2018, 08:00:55 AM »
Most common problems with these wiper systems are compounded or stacked issues. High resistance especially near or at the connector for the motor, the motor itself and connections at the module are the main points of high resistance. All it takes is a little bit of resistance and pinpoint tests become a cat and mouse game. As soon as you unplug or wiggle or backprobe connections the path of least resistance changes and the mouse moves to a new place. I would recommend repairing or replacing the pigtails at the wiper motor and disassembling and cleaning the connections at the module.

I was going to actually start today by replacing the park switch connector, as so far it seems everything is revolving around that(no mist, and no delay), the more I thought about it, the more its seems there is a break somewhere along the wire run for the blk/blu park wire.
Current Vehicles:1985 GMC K10(Daily)
1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
1991 GMC K2500(under repair)

Offline 1967KaiserM715

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Re: Wiper issues
« Reply #37 on: October 21, 2018, 11:40:38 AM »
I replaced the park switch connector, by splicing in a used connector to the old harness near the junction block. That seems to have solved my problem, everything seems to be working as it should right now. I'm going to use the truck for a few days and see if the issues pop back up.

There doesn't seem to be anything visibly wrong with the old connector, but I do recall cleaning off a fair bit of corrosion when I first started having problems.

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Current Vehicles:1985 GMC K10(Daily)
1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
1991 GMC K2500(under repair)

Offline 1967KaiserM715

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Re: Wiper issues
« Reply #38 on: October 25, 2018, 04:01:07 PM »
I've used the wipers several times now, and there seems to be no issues now. Replacing the Connector End for the Park Switch on the Wiper Motor appears to have solved the issues.

Many thanks to bd and VileZambonie for their help and guidance, and to all those that also helped.
Current Vehicles:1985 GMC K10(Daily)
1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
1991 GMC K2500(under repair)

Online bd

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Re: Wiper issues
« Reply #39 on: October 25, 2018, 05:03:52 PM »
Happy to hear you got it solved!
Rich
It's difficult to know just how much you don't know, until you know it....
In other words... if people learn by making mistakes, by now I should know just about everything!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline VileZambonie

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Re: Wiper issues
« Reply #40 on: October 26, 2018, 04:20:59 AM »
Good deal!
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