Guys,

I have a 69 Z with factory gauges in the console. The problem just happened last night...When I turn on (pull out the parking / headlight switch) my gas gauge goes to empty and my temp gauge pegs out at top (hot). When the light switch is not pulled (or on) the gauges work fine. I also noticed when this happened that my lights in the gauges do not work at all either, while before this happened they worked. As soon as you pull out the switch the gauges immediately react. The other two gauges are unaffected. As soon as you push the switch back in the gauges go back to working.

Do I have a bad switch or a short? And if so any ides where? Before I get into tracing wires, If anybody has any thoughts of exactly where to start or pointers, PLEASE let me know.

Thanks guys

sounds like you have feedback of excessive voltage going to your gauges.. check your ground in the dash. If its feeding through, then its looking for the shortest link to ground and thats likely your gauges

Nantooch,

The ground that you are talking about, I assume, is the ground for the gauges? Or is this a different ground? Where should that be, under the console or where in the dash?

Thanks for the help, let me ask this, do you think that a malfunctioning temp gauge could cause this problem? This past winter I updated the entire cooling system, except for the gauge ( new water pump, heater core, new coolant, and new sending unit). I noticed that this year when I got the car out, the temp gauge was all over the place and when the car was at operating temp, the gauge was reading hot, when it was not hot ( I checked the temp to see that the gauge was wrong). When the car is started, when cold, the gauge is only reading 1/2 way on the gauge, not on the cold side.

My question is, could the gauge being bad cause this original problem that you responded back to? Before I get into tracing the wires for the gauges to find the ground that might be loose or bad, while I have the gauges out should I replace this temp gauge? Does the gauge sound bad since it is all over the place?

I am just trying to find out as much as possible before I get into the wires, this is not my strong suit.

Sorry if these are dumb questions.

Ron

Responded to your email. :)

Thanks Nantooch. I'll let you know what happens.

I suspect your fender ground near the battery is poor. It's probably good enough up to a point and then the whole body ground potential changes when a load is placed on it. Beware though it may be saving your bacon if you do have a short somewhere.

I'd check the battery drain posts in the archives of this forum for a procedure to check the current load with a test lamp. Then clean and repair the ground. Check the clamp as well. A good start would be to measure the voltage drop between the fender and the negative post. If you see a drop, as I think you will, you can probe around the ground lead to find out where the drop is. None of your fuses are over-sized are they? Hate to see your money pit go up in smoke if you do in fact have a short circuit somewhere and a hungry fuse to feed it.

I had the same problem with my 69 Z. Check the ground screw on the back of your gauge, that was my problem. It was loose, this solved the problem.

I hope yours is this simple.

Nashcar

OK, quick update on this problem.
The problem turned out to be a bad ground at the gauges. Made a new and GOOD ground and the gauges all work, the lights now work in the gauges and the temp gauge is registering correctly (not registering hot) when it gets to operating temperature. Since I have it all apart, I am also replacing the low fuel sender since that was not working and since I did have one, I am replacing it too. Thanks Nantooch and nashcar & dnult. This was also a good time to check the suggestions of the battery ground and fuses. All grounds are good and all of my fuses were and still are correct size.
Again, thanks to all.

Ron

hi guys Im new here, but old to the game, still have my 68 rs conv. Im getting it out and driving it as storage has not been too friendly, I do notice that my tailamp fuse pops as I pull the knob,turns work, headlamps work as do the flashers. I did evict some mice from under the rear seat, and the trunk. Im looking to see if they chewed some wire to the talilamps, seeing that the blinks and emerg work is there still yet another wire to the tails also? I pulled the rear bench and am looking at takeing the left side int arm restand side panel to look for damaged wires. before I do where else can i ck first? I am looking to replace my 69 asap if that anserwers my user name....