Here is a weird one for you...

[NOPHO84K30]

Sometimes when im stuck idling in traffic my wipers will just start swinging back and fourth with no input from me.
It happens on and off nothing i do is different when it happens. Also sometimes just shifting from 1st to 2nd they'll do it.
Now my column where the turn lever with wiper control is, is broken and the lever flops up and down for the brights because the cover is missing. Now why would my idle or shifting cause the wipers to turn on.

 

[chengny]

It happens because the wiper ground lead is shorting out somewhere (most likely inside the steering column). Power from the fuse block is always available on the positive side of the the wiper motor windings. Normally, there is no path to ground for the negative side of the windings. So, without a complete circuit, the motor doesn't run and the wipers sit still. If you want the wipers to run, you twist the end of the stalk which is connected to the switch in the column. The switch is connected to ground on one side - twisting the switch closes the contacts. The motor is then grounded and runs.

But sometimes, especially in tilt columns, years of turning and tilting cause the insulation on the ground leads to get pinched or just wear away. Then, if the copper inside the insulation is allowed to touch a ground point inside the column - the wiper motor runs on it's own.

 

[jetman]

That explains it. My '83 with delay wipers would just start running randomly in the middle of the night with the key out of the ignition. Scratched the H out of truck's windshield. Rather than hunt around for the offending issue I simply unplugged the wiper motor leads, plug in when it rains.

 

[NOPHO84K30]

Ok good to know next project might be the column rebuild

 

[chengny]

Check one other thing before tearing into the column: if you have intermittent/pulse wipers, try replacing the solid state module. It is mounted under the column - it is supposed to be clipped to the wiring harness bracket but is is usually hanging down:

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If those modules go bad - and they eventually do - they can make the wipers act like they're haunted.

 

[NOPHO84K30]

Ya mines hanging down. It sits on the bottom of the dash. Now i do think thats not working because the wipers only work on high no intermittent. So ill start there thx for the replys

 

[Camar068]

Not as bad as yours but I have to rotate the knob all the way back to stop them. I'll be searching around the forum this weekend to try and figure it out. Been dealing with it for 2 yrs.

 

[highdesertrange]

instead of just buying parts and hoping that's the problem. why don't you find the trouble shooter flow chart, find out the real problem and fix it. highdesertranger

 

[NOPHO84K30]

Thats a good point highdesertranger, i need to up my diag ability. Throwing new parts at it till it works only goes so far. Especially when most new parts are crap for lasting very long.

 

[highdesertrange]

thank you Justin. the end result is always better and usually cheaper if you follow proper troubleshooting. highdesertranger

 

[chengny]

instead of just buying parts and hoping that's the problem. why don't you find the trouble shooter flow chart, find out the real problem and fix it. highdesertranger

Ideally, that is the right way to solve a problem. Blindly changing parts gets expensive and nothing is learned about the system being repaired.

Problem is, sometimes these "shotgun repairs" work - especially when multiple parts are changed at once. I guess since bypassing the diagnostic procedure and jumping straight to part replacement is easier - it justifies the occasional hit to the wallet.

But, in this case, the proper diagnostic procedure was basically followed. The problems described were both specific to wiper circuits equipped with the delay option. The primary complaint was that the wiper motor would intermittently start - without any action on the part of the operator.

The diagnostic charts provided by GM for the windshield wiper circuits cover many issues. They offer possible causes/solutions for: the wipers not starting at all, operating only on high/low speed, running at the same speed - regardless of switch position, failure to return to park position, failure to shut off and mechanical problems like the motor runs but the arms don't move. They don't mention anything related to what the OP asked about.

They do discuss intermittent operation, but that only refers to the the wipers repeatedly starting/stopping with the switch in a run position.

Point is; nowhere in the diagnostics does GM address the issue of the wipers operating independently of the operator on an intermittent basis.

Delayed wiper operation, wiring diagrams and diagnostics for 83-84 C/K series:

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Delay diagnostic:

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Delay diagnostic refers to this - standard wiper diagnostic:

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1986 delayed wiper wiring diagram and diagnostic:

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BTW - For jetman: I'm not sure of which model year the wiper switch was moved to the column, but I think it may have been in 1984. So, its possible that the module location, as shown above, doesn't apply to your 1983. If your switch is dash mounted, the delay module will be hardwired directly to the back of it. Like this:

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