VetteHalen

so, this is a new one... my wipers didn't come one last week after i got caught in a mild sprinkle. after some sleuthing, i discovered that they won't come on when the hood is closed. that is, they won't come on when the "hood ajar" switch is depressed. [side note: is there supposed to be an audible "hood ajar" sound or perhaps an indicator lamp on the dash? because... i haven't heard/seen either since i've owned the car]

anywho, i turn the engine on > open the hood > turn the wipers on and they work. but when i press the hood ajar button, i see a spark and the wipers immediately stop. spark equals a short somewhere, right?

and, when the hood button is depressed the AC fan stops working. release the button and the wipers and fan starts up again.

SO... any suggestions on where to start looking for this suspected short/electrical gremlin?

AND, what if i just disable the switch to be "open" all the time? that's just treating the symptom and not the problem, right? i did notice when the wipers are on the two wire connectors on the hood ajar switch get pretty hot. and that's probably not good.

[EDIT: car is 1980]

Danish Shark

The spark occurs because current is flowing through the switch at the time it disconnects.

Always remember to write what year Corvette you have when asking questions.
The error was probably always there, a previous owner connected the wiper and fan motors at the wrong source?
The switch gets hot because it wasn't designed for the current needed to operate the wiper and fan.

speedreed8

sounds like its providing a ground path for the motors to work. what year???

mark6669

Check the ground wire by the starter should be on the starter bolt or lower bell housing bolt depending on year . They work with hood up because they are grounding thru the alarm circuit.
Mark

Easy Mike

There is no "hood ajar" switch. What you're fooling with the part of the factory alarm system.

What model year?

VetteHalen

car is 1980.
(sorry - i assumed everyone could see it under my name above my picture)

- ah, makes sense that this switch is part of the alarm system (which has been "disabled" since I purchased the car. i even left the alarm horn disconnected. i never bothered with the alarm)

-this is a new-ish problem, but i'm not sure how long it's been going on since i haven't tried the wipers in a long time and didn't notice the AC fan. ...maybe a couple of weeks? more maybe?

Besides the alarm horn, are there any other alarm components for me to inspect for bad grounds?

'76stingraycolorado

My '76 is now doing the same thing. The wipers won't turn on when the hood is closed but come one once I release the hood. Just curious if you ever solved this problem and what the fix is.

Thanks!

'75

As stated above, check the black ground wire at the starter, it should be connected to a starter or bell housing bolt. That is the ground for the wiper motor and blower motor.

qwank

there's no alarm horn. you may have an after market system that is getting power or ground from the wiper circuit
EDIT: dammit, old thread

'76stingraycolorado

I'm still dealing with this issue.

I checked the ground wire (big black cable/wire) at the starter. It is attached correctly.

However, I noticed that the hood switch (alarm switch) just gets RED HOT when the hood is open and my wipers begin working again.

Any chance the problem is the switch itself? Would ordering a new switch solve this issue?

Otherwise, I'm at a loss. Can't figure out my this would suddenly start happening. Also, if there was a ground wire issue at the starter, wouldn't this cause more issues than just the wipers blades to stop working?

I'm leaving for Bowling Green in a few weeks and I hate to have to open my hood simply to get my wipers to work.

Thanks!

'75

Here's what I would do for at least a temporary fix. Unhook and insulate the wires from the hood switch, tape them up. Then run a ground wire from the windshield wiper motor housing to the engine, then I'll bet the wipers work ok. Also, the ground wire at the starter area is a small black wire that is supposed to ground the wiper and the blower motor, not the big cable.

'76stingraycolorado

For tonight, I just removed the switch and taped the two wires together so my wipers work.

Is this a bad idea?

Also, I will recheck for the small, black ground wire for the wipers on the starter.

Thanks!

'75

Is there a black wire attached to the wiper motor?