Dash lights / Wipers 1981 Vette

[gambit]

Hello Group of wonderful talented vett people. Thanks for all your help thus far, its done wonders!. Im having some interior electric problems. My Dash lights didnt seem to work, I was getting Lights on my speed and tach, wiper knob and the transmission gears park drive etc. No lights on the AC/ HEATER or in any of the other gague cluster of oil, temp, battery etc. (the check engine light sure doesnt mind working any time though) hehehe. I tried to use my wipers tonight in a rain storm and NO LUCK nothing happend. I could hear a clicking behind the passengers seat every time I would turn the switch on but nothing would happen, tried many times. Then my oil pressure and temp gagues panel lights came on by themselves, every gague there had lights and the only place I didnt have them was in the Heater / AC controlls, and im not even sure Im supposed to have them there.

Got any ideas why I would be having a short in my lights, and where I might track it down? How about my wipers, it sounds like some sort of relay with the clicking behind the seat, but thats an odd place for them. then again this is my first corvette so how would I know whats odd . : )

What say ye ole gods of corvettes?

ADDITION, The interior lights work when I turn the headlight knob but dont work when I open either door. I also was told the light would fade out till it turns itself off but it doesnt do that either, possibally because it doesnt work with the door switches, only with the headlight knob. Got any clues?

 

[TJay]

gambit, you like to give us a challenge. Two questions before I write a complete page on what to do with the wipers first. It sounds like the wiper control module, if it is we can at least get your wipers working for you on all speeds, (by-pass) as the module is very hard to find anywhere, and if found very expensive. I need to know these questions, without knowing your skill, please understand I'm just try to help, if you find these questions simple. Once I understand the skill part I'll assume your better than me at this repair stuff and I'll be asking you.

Question,- do you have a volt/ohmmeter and know how to use it.
Question,- does your wiper washer work. (works from control module also)

Once you reply I'll take you through the wiper repair as soon as I can. or maybe some else will jump in to help also.

 

[gambit]

Hey bud, thanks for the response. No I dont have one but I do know to use it and can get one. How expensive could a module be?

I didnt try the wash feature, stupid question but how do I get it to work, push the button in? Its an old style, the knob turns clock wise, and slides down 3 positions which I assume are high medium and low, adn I though the turning clockwise was for the wiper delay. how does the washer work?

 

[TJay]

gambit, push it in I believe on a 81. The 3 position is, slow-high-park. And you will need a volt/ohmmeter, they are really cheap to buy to use only on your car. (not a cheap one though if used on house current) Once we get the wipers going we can tackle the other dashlight issues. The module I have only seen on e-bay, $200.00 - $300.00.:cry Once you post about the washer I'll post the repair, and it is a long circuit test, so i'll post it Friday morning, (I have to run it (test) through my head and I don't own a 81 but can read the circuit drawing so we will be talking wire color's which will make it easy for you to follow)

 

[jdp6000]

The heater AC control does not have a light built into it. There is a light in the center bezel just above the heater vents that shines down on it and the ashtray. It has a bulb which is probably burnt out. You need to take the center cluster out to get at it. The cluster is held in by two screws left and two screw right. Not sure if there is two at the top...maybe but you will see them.Important...there are also two screws that hold the center cluster to your consol and can only be accessed by removing the consol side panels.

as you pull the center cluster out you will see two wires that attach to a bulb holder at the top. The cluster will only come out so far unless you un screw these wires. It should however pull forward far enough to get a new bulb it. Heres the problem many vettes are missing these wires or the bulb plug is busted. Take a look. I recall this bulb to be slightly bigger then the typical ones in the cluster.

My pulse wire switch does not work either but my wipers still work at one speed. So you may have two problems the wire switch and the pulse module. I replaced my switch and did get the wipers to work they just don't pulse.

Best of luck,

Jim

 

[Yoda]

Jim is right about the heater/air-conditioning switch & ashtray light being in the dash above the heater/air vents in the center bezel.

A word of caution when pulling out your center gauge bezel... be careful and use a small screw driver or putty knife to help the light fixture in the bezel clear the dash. All the ones I've seen have very sharpe metal around the light fixture and will tear the dash pad if you are not real careful

Also the light for this is a special light with a magnifier tip on it. If you use a regular type bulb it won't provide enough light to see anything. I don't recall the bulb # off hand, but there is a page in the L81VetteRegistry that has all the bulb numbers. If I remember correctly it's in the Tech section under "Maintenance"

Bud

 

[gambit]

yup i tried pushing it in, twistin it, poking it, pullin it kicking it and nothing happened : )

 

[TJay]

gambit, here's what you can try to repair your wiper issue.

First check the motor, this is for the motor with a 3 prong plug on the front, a separate black lower on the front, and the pink delay wire on the passenger side of the cover.

Make sure the black ground with is grounded correctly (check with an ohmmeter) and leave it connected. Disconnect the 3 wire plug (Just for your information the diode between the 2 wires is supposed to be between the top 2 wires (purple & white). Check that the plug isn't upside down)

With the plug disconnected, apply +12V to the middle prong (white wire on the plug). Ground the top prong (purple wire on the plug) and the wiper motor should start running in high speed. Add a ground to the bottom prong (grey or gray/black wire on the plug) the motor should now run in low speed. Remove the ground from the top prong, leaving the other 2 and the wipers should park. If this is what you get now move on to the next step.

Next check the switch. After getting it out of the dash (real pain) look for obvious reasons to suspect it. (loose wires, burnt smell everything connected tight) Now check that things connect & disconnect as you change switch positions.

There's a 6 connector & 3 connector plug on the back of the switch. The 6 connector location on the switch is what you should look at close, as it's broken into 4 & 2 sections. With the knob pointing at your lap, and looking down at the 6 wire connector on the top, the grounded contact is second from the left (goes to the black wire on the plug)

The left most contact shorts to ground (second contact) when the wiper switch is pushed in (for washer)
The 3rd from the left shorts to ground at the high speed position
The 4th from the left shorts to ground at all switch positions except off.
The 5th position from left should not be in use.
The right most contact is for the light bulb, shorts to ground all the time if the bulb is in and good. (check for good)
The bottom 3 contacts are probably for controlling delay & interval & misting from what I make out on the electrical drawing...?

Now with an ohmmeter, check connectivity on all the wires going from the switch to the controller, the controller to the motor and the switch to the motor. This is to verify the wire harness is ok.

If everything looks good so far with the harness check, you should narrow it down to the controller assembly being bad. (This is the part thats hard to find and expensive if you do) Here's where we bypass / eeliminate the controller assemby. (until you find one or you can leave it) Some Corvette Suppliers make a thing to do this bypass ($10.00 I thing) but we can use a paperclip for now (I did say for now as this is just to get your wipers/washer working for now. I'd look for the controller or the $10.00 bypass plug) or make your own. (simple just do what we are going to do with the paperclip)

Make sure the key is off, remove the controller assembly at the controller assembly plug, short (jumper) the white & brown/white wires. (paper clip between them) This will get power to everything, and give you low & high speed wipers. Make sure to cover the jumper somehow, since it will be hot when the key is on... (CAUTION HERE, TAPE, WRAP ETC.)

To make the washer pump work when you push the switch in, short (jumper) the pink & pink/black wires.

You should now have High & Low speed with Washer working until you decide or find a control module, but at least everything will be working from your dash wiper switch. REMEMBER.. if you can get a the same plug, you can use wire to jump it the same way and just plug it in....

I hope the wire colors match on your car to the circuit drawing I have but it should be correct, just print this out and take it with you so you can follow along during the test.

Good luck and keep us posted, your dash lights will be next.

 

[gambit]

I now have semi/quasi wiperage. Not sure how, but here is what happened, and let me know if you have any further feedback.

I thought I was going to be smart (which is redneck for lazy) and skip the testing and just try the jumper thing on the controller assy. under the rear compartment, figured if that fixes it then so be it. It didnt. I shorted the wires and switched on and the same thing it would just click click click and nothing. So I gave up on that and looked under the hood. The motor did have a 3 wire plug going into it so I pulled that back off, it had dry rotted black duck tape hanging off of it and when I looked closely I saw what I thought was a jumper crosing out two wires, I now know from re reading your notes that it is a diode, and as a matter of fact, it looked like a diode at the time, but it also looked like a little 10$ thingy that one might short out two wires with : )
I just sorta pressed that in and plugged it back up, making sure it was right side up, as I forgot to check to see how it was plugged in before, then I hit the switch and volia, wipers worked, so I pulled it back off and taped it up real good and sealed with elect tape, and plugged it back up and it still works time after time, and my Controller assymb. does not click the way it did before.
Two things, I dont have the delay, which I dont really care about, and the washer doesnt work, but there is fluid in the tank. off is at the bottom, if I push it down and hold it down, that should be WASH since it only stays on as long as I hold it. up one and up two give me the same speed and up three which is all the way gives me what I am to belive is High, but I dont think Ill drive in anything other than light rain at the speed it give me or Ill end up in sombody else,s tailpipe.

Any idea what I might want to try to get the washer going? that may come in handy sometime.

Thanks again for all the help, it is MUCH appreciated.