[rapsag]

I was just out driving my '34 Mercedes 500 K replica with a Camaro 350 drivetrain. A/C was on and it sudenly went off (blower stopped), so I figured it was a fuse and kept driving. When I got home, I could not shut off the engine with the ignition key. Did not matter whether in off or acc position. Seems strange that both would happen at one time. So I pulled the coil lead to the distributor and shut it down. Re attached the coil to distributor and started engine with the same results also A/C blower is dead in either position. I have noted recently that the blower fan did not go off with the ignition switched to off. It had previously gone off as expected. It did not occur to me that the ignition switch might be faulty. Hope that is a clue. I have checked the voltage at the coil with the distributor lead removed, and it is 12 volts on both the hot side and the ground side. Also the guages are on with the ignition switch off. (so I pulled the lead from the fuse box to avoid battery drain. It is 100 degrees outside and worse in my garage so have not explored the fuses etc. Anyone have this problem before? Doc, are you out there today? rapsag

[rapsag]

Does anyone think it is just the ignition switch that needs replacement? Or do I have something reversed somewhere? Could not find a blown fuse.

[larkster]

did you try disconnecting the blower motor sounlds like power is feeding back somewhere holding ignition on

[rapsag]

Did not check it, but will do so. It is a vintage air.

[rapsag]

disconnected the plug for the vintage air. No change. Coil was still hot. I think it may well be the ingnition switch. I suspect it was not changed out when the car was built. Not sure how it is positioned (lots of wire jumble under the steering column). Not sure I would have further battery drain as long as the gauges power line is pulled, but just to be safe, I pulled the ignition fuse and that of course took the coil off line. What do you think? rap

[larkster]

could be ignition switch. Just seems weird the blower motor stopped at the same time.... The only way to verify it isnt the ignition switch is to test with an ohm meter with the ignition switch off see if there is still continuity with the power supply of the ignition switch..
This is why wiring is so hard to diagnose. because it depends on how it was wired and how many things are tied to the ignition switch directly. and not through relays or switches. If its not the switch,Just going to have to test each circuit at a time. If it is the switch i would see why it failed. After you put the new ignition switch in turn all accessories on and put a meter on it and see how much amperage you are pulling through that circuit.

[rapsag]

Good advice, The fuse certainly did not blow. During construction the Vintage Air and other acc. had to be adapted to the Camaro harness,so I suspect there may be a lot of crimped leads that may not be solid and jiggling around while on the road might cause some arcing and heating up at the switch. Will check it out and let you know. I will have to drop the stearing column to get to it all. It is 104 here now so it will have to wait for an early morning approach. Thanks again.

[rapsag]

Change out the ignition switch module (ugh!). Not the answer. Also have noticed that the fuel guage is on even though the ignition fuse is out and the guage line to that fuse is removed. The lights, courtesy lights all still work and switch off properly.
Somehow the A/C going off is the common denominator in this puzzle. There are tons of redundant wires from the old harness under the dash that went to the old dash module and are no longer used. So I baffled at this point. Where to begin? I even put the battery charger on and it shows less than a full charge on the battery (it is a new acid glass matrix battery) at about 12.3 volts, will keep it topped off with the charger.

Meanwhile, how can there be current going to the ignition when the switch is off?? Everything worked super well before the A/C blew. rap

[NXS]

Hi Tulsa!

What alternator do you have? Does it have an electric fan?

I'd contemplate a rewire of the ignition system/coil.

Is the fuse box hot when the key is off? Or does it stay hot after the engine is turned off?

[78novaman]

Hacked wiring is always bad, and it sounds like you have a mess on your hands

You said it was hot and you had the AC on. This creates alot of heat. Hot electronics draw more current. More current creates more heat (I think you can see how the problem compounds itself). Heat & excess current are very bad for a hacked wiring harness. If I were you I'd check to make sure the fuse box or a distribution block didn't melt.

It sounds like you definitely have a short somewhere. You may want to check your solenoid as well. If it's fried closed (shorted) all the time then the ignition key won't shut it off. Does the header run close to the starter & solenoid? With the temp around 100 & the air on that is one very hot engine bay. Could have fried the solenoid closed (shorted on) all the time.

Re-reading everything makes me suspect the solenoid even more. The lights wouldn't be affected because they are always live anyway. Depends on the year of your camaro harness whether the gauge cluster is through the ignition switch or from the solenoid. Your car continuing to run when you turn the key off is telling me that the solenoid isn't clicking open when power is removed. Just seems strange to me because I've always seen a solenoid fail preventing the car from cranking or starting.

I know I'm not in the same league as Doc, but I'm trying to fill his shoes while he seems to be taking a sabbatical

[rapsag]

This am I did the following checks. With the key off (out), only the ignition part of the fuse box is hot. The A/c-heater circuit is cold, infact the only other circuits that are hot are those that are supposed to be (lights, courtesy lights etc). I inspected the Vintage Air fan control, and it controls also the thermostat feed and manual compressor on (a toggle switch on the dash). I am about to put the meter to it and see if any leads are hot (not supposed to be?). Then I am going to disconnect it (five leads) and see if things get corrected. If so, then will call Vintage and raise a little hell for a new one and let them know what happened. It all seemed to start with that system going out.
However, as you suggested, will check the solonoid (how do I do that without taking it out????). The solonoid and starter are spanking new in appearance as is all the rest of the car, and does not appear to have had lots of hot exposure. It even has a heat shroud around it to deflect the exhaust heat. This car is essentially unused since 1990 and the a/c was never loaded or used (Las Vegas show car, driven with top down in nice weather--or so I am told)
Will report back. And thanks a lot for all the input. rap

[rapsag]

A/c switch has no current even when ignition turned to Run. The A/C fuse is good and current at the fuse box. So somewhere between, there must be a separate fuse or connector.. Meanwhile the ignition is still hot in the off position. Looks like it is possible to have flees and lice at the same time after all. Something is fried somewhere, just can't locate it. Will check the solonoid next as you suggested. Any hints on how to test it on the car? Remember, the starter still works when everything is back together, just won't shut off. Is that possible with solonoid frozen closed? Wouldn't the starter just keep going? help!! rap

[78novaman]

Unfortunately, you can't take the solenoid off GM starters.

Sorry I forgot to put in the solenoid check (it was late for me, not usually up after midnight ). It's easy to check. With the key to 'off' you should just have the one post from the battery hot. The other 2 posts should have no power.

What year is that camaro harness?

[rapsag]

I have more news. Thanks 78Novaman, I think you are going to be right. When I put everything back together (except the A/C switch). The dash gauges are still on at 'off'. When I turn to 'run' the usual accessories come on, i.e. radio, But when I turn to 'start', NADA, and the voltage gage goes to bottom and the temp guage swings all the way to hot. Suggesting to me that there is a short in the starter solonoid as you suggested. There is about 6 volts at the hot lead of the coil as well in 'off' whereas it was about 12 before when this first happened. Remember, right after it happened the first time, I could start it again but not stop it. So I suspect the solonoid. Have not found out yet what the A/C problem is but it is separate..
Unless I farkled up the new start switch? (I checked and the harness is in properly). Will get after the solonoid asap.

[rapsag]

With the key in 'off'. There is about 6 volts at one of the lesser wires on the solonoid. Same as on the hot lead of the coil. Does that qualify as a bad solonoid and thus the feedback is from the solonoid thru the coil and to the ignition circuit? There is 12 volts on the battery lead as expected.
I hope this does it for that problem. Initially after the first time it kept running at shutdown, there was 12 volts at the coil (both leads) but it also would start again. Now only 6 volts and it does not start or turn over.

Should I disconnect the coil leads and recheck the solonoid to see if the 6 volts originates there, before I install a new one? Will do it anyhow just for confirmation and get back with you again.