I pulled the car out of the garage today to wash it. Everyhting seemed to be working alright. Washed and dried the car and attempted to put a new 20 amp fuse in the courtesy light fuse holder. Didn't get it in.

Came back out to the car about an hour later and started it up. Immediately noticed the generator light came on and the electric windows won't go down. Turned it off and went about my business. Came back about two hours later and started the car. Same problem plus some.

The light doesn't come on immediately. It will idle with no charge showing on the volt meter. Give it a little gas and the light comes on.

I also noticed that the red dash warning lights aren't coming on, the clock isn't working, the oil pressure gauge pegs out to the right when you turn the car off (it usually stays at the oil pressure reading that the car was turned off at) and if you give it a little gas it goes to the center but doesn't really seem to be working and the tach is now all the way to the right.

The hazard flashers come on and flash, the blower for the a/c works, the a/c is working, the headlights come on, the highbeam indicator in the speedo comes on, the rear window defroster light comes on, the turn signals work, etc.

The generator circuit, which is the attached picture, has all of the items I am having a problem with going through it. I need to check the fuses tonight but I have suspicion that the problem is the alternator.

http://www.corvetteactioncenter.com/...&postid=234368

Any comments

Thanks.

Bob


[Modified by Bobchad, 8:58 AM 6/23/2003]

 

Well, first off, replace that fuse, and take a voltmeter and see the voltages on each side of EVERY fuse that they are the same....sometimes a fuse gets corrosion built up in the clips under there, and gets hot enough to melt the lead solder inside the fuse, opening up the circuit, and in fact the fuse still LOOKS good, but i'ts NOT>>>>>>

been there seen that, frustrating thing about them style fuses for decades now...

IF you get proper voltages all across the board, we can talk then...
it may be as simple as a mis-adjusted or defective ignition switch....NOT the mechanical thing in the column the key goes into....but the electrical part on top of the columb that is a bitch to get to....

GENE

 

Will replace them all and post what I find.

 

Put your voltmeter across your battery terminals. With engine off you should read 12V. With engine running at 700RPM or more you should read 13V to 15V. From what I have heard it is normal to see this voltage drop when your engine is running below 500RPM or so. With your engine at 700RPM if you see less than 13V chance are your alternator needs help. Let us know what you find, good luck.

 

Looks like I am going to have an excuse to but a voltmeter.

 

Your not a man until you own a multimeter LOL :cheers:

 

Bob, do yourself a favor and do NOT go to Radio Shack for your meter, DO go to a pawn shop...hock shop and pick up a nice Mack/Fluke meter in yellow or gray case...they are the BEST...and pay not over 50 bux....IF it's working...

with probes....that Rat Shak crap I carry in the car for roadside assistance...nothing more....

GENE

 

Thanks for the input guys. The best part of having the car on days like today is getting to buy the tools. I had been getting by with a test light.

 

I had a minor miracle happen today. The 8 year old wanted to spend some time with his old man. Will look at it on Wednesday and post. Thanks again.

 

Hey I have that exact same problem. Only difference is that after I put the fuse in something start clicking and then 30 seconds later the fuse goes. Everything works during that 30 seconds. I have replaced the alternator.

 

Whcih fuse? The 10amp gauge fuse?

 

The 20 amp fuse. Also, did your horn work before this?

 

Yes. Still does.

Which 20 amp fuse are you talking about? The courtesy light, cigarette lighter circuit?

 

Yes, the courtesy lamp, lighter fuse (which now that I think about it is a different circuit than the electric windows circuit). So I guess I have more a similar issue than the exact same issue.

 

Not necessarily. I have that fuse out of my car because the courtesy lights aren't dimming. I will try replace that tonight and see if it solves the problem. This is strange since the problem areas appear to be on a different fuse than this.

If yours is blowing the fuse after about 30 seconds I would suspect that you have a short somewhere.


[Modified by Bobchad, 1:55 PM 6/25/2003]

 

Hmm. Yes very strange. I have heard that the alternator light on and no volt read on the gauge (in my case) can be cause by some part in the alternator that has to be replaced even though the alternator is new. Some compatibility issue there. Have you heard of this?

 

I think you might be talking about the voltage regulator.

The clicking sound suggests to me that you might have a short somewhere in the circuit. Where in the car is the clicking? I would supect either the courtesy light delay or the cig lighter. Both use a heated element to cause their circuits to open. As to the courtesy light delay, it uses heat caused by electricity running thorugh it to open the circuit and turn off the lights. Supposed to open after 20 - 30 seconds. If broken, it may not be opening and overheating the circuit causing the fuse to blow.

Can you disable this portion of the circuit only. On my 77 the unit that does this is hidden up under the dash pad between the speedo and tach. Yours may be easier to get to. The driver's side door switch has three wires coming off it, with one going to the unit. I'm going to disable this and see if I can take my courtesy dimmer out of the loop.

Of course the cig lighter has a similair concept to heat the element. Have you tried pulling the cig lighter to see if the problem goes away. If that doesn't work, pull the tunnel cover and remove the hot wire from the bottom of the lighter. Try again.

There is a third circuit coming off this fuse as well. But I can't recall off the top of my head.

 

The third component on this circuit is the clock, another potential problem as these things go out all of the time. I replaced mine with a quartz clock.

My understanding of the old mechanical clocks is not Vette specific but from what I know they have a mechanical spring wound occasionally by an electric motor. This could also be a source of the problem.

I got under mine tonight and as expected found the 10amp gauge fuse blown. Not as expected, the assortment of fuses that I bought several weeks ago has every size you can imagine except 10 amp so it's off to the hardware store.

 

Any luck with the new fuse? Before these issues started a few weeks ago, the clock (quartz like yours) worked fine. There is one more piece of the puzzle to my problem. After turning the car off, the key buzzer stays on even though I have removed the key from the ignition. It will stay on for 30 seconds to a minute. I am hoping this isn't proof of the dreaded-column-wiring issue. All these issues appeared at the same time but maybe they are not related.

Also, it sounds like the clicking is coming from underneath the center console.


[Modified by 79C3, 12:14 AM 6/26/2003]

 

10amp fuse fixed mine.

I would bet that your problems are related in some fashion. Too much of a coincidence.

Something appears to be generating more draw than the fuse can handle and is blowing it. Can you disconnect the buzzer for the key. If it is the same as on my car, it is on the same circuit as the 10 amp gauge fuse. On my car it is mounted to the fuse box and was disconnected before I got the car. If I plug it in, it buzzes all the time.

You need to start disconnecting the items on the circuit to see if the problem goes away. Do you have an electric schematic that will allow you to determine the wiring for your 79. You need this http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=34215&it em=2420703208 manual but only for a 79. I use mine all the time.

I would suggest a voltmeter for the readings but the fuse is blowing so fast that it serves the same purpose.


[Modified by Bobchad, 8:18 PM 6/25/2003]