rustbucketrex

My '90 CRX a few weeks ago, after I got my A/C working again, began to smoke from around the steering column after about 30 minutes of driving with the A/C on(on really hot afternoons only). I took the dash apart looking for any burnt wires(I could smell the insulation burning off of some wire before the smoke started)but could not find anything. After searching the archives for a while, I narrowed it down to the ignition switch, found some burnt connections and replaced it over the week-end. The white/black wire and the blue/white wire both had melted solder connections and the white/black wire insulation showed signs of high heat(discoloration). In the archives most faulty ignition switches caused non-starting issues and car shut off problems, but a few had smoke like I did and some were electrical load related(stereo and fan use).

I did not have any other symptoms and it only happens with A/C running on hot days(95+). I have not found in the archives if replacing this switch solves the problem or will it happen again under the same conditions and I will have to replace the switch again, only a few people will be able to answer this if it happened to them, but I plan on updating this thread with my results as I continue to use my A/C through the hot summer(45 mile
1 way commute).

My theory is that on hot days running at 70-75 MPH, even with air flowing through the radiator that the fan is coming on or the condensor fan, or both,in addition to the blower motor and it is too much for the old wires to take. My coolant temp has not shown any increase on my gauge but you never know.

My hope is that a 19 year old part could not handle the load ,but a new part can and that will be the end of it.

sanimalp

you should check to see that there is a properly rated fuse for the AC before going any further, or if you did some custom wiring, make sure that is properly fused and grounded to an area that is not a common ground with something like the ignition switch.. If you just got the AC working and all of a sudden you are melting ****, it means the wires are carrying way too much current, not that they are old and crappy.

Ignition switches have been known to fail as you have shown, but it seems to be fairly rare in my experience. Most ignition switches that I have dealt with actually die from internal contact fouling or solder pooling strangely on the contacts on the back of the switch.

Protected wiring like that doesn't just wear out, either. By that I mean the interior of a car is a pretty good place for a wire to live out its life. It isn't exposed to terribly excess heat or cold, and virtually no moisture unless you live in a really humid area.

before installing the new switch and catching that one on fire, unless you can see some sort of failure (contacts shorted, wires chewed up and shorting) on the old switch that caused it to melt, you might want to take a moment and determine everything is properly fused and grounded, because it would suck *** to melt another brand new ignition switch.

rustbucketrex

Thank you sanimalp for the response, I will check the fuses, wiring and grounds when I have the time. I have not done any custom wiring, I did a motor swap in April and used a Rywire harness, but I will recheck my grounds.

I have already swapped ignition switches and left the steering column cover off to watch for smoke and to feel the wires for heat build up. On Monday it was cloudy and cooler and the A/C did fine without smoke. On Tuesday it was hot again, and after about 20 minutes of use, I saw a small wisp of smoke, and shut it off. So I will not use it again until I get a chance to check out the wiring, fuses and grounds.

8dxhatchy8

same thing happened to me out of no where bout a week ago, my car would not start or stay running, bought a new one (60 bucks autuzone) starts up fine now....

mjfubar101

Sucks I could of sent you my basically new ignition switch cheap I got it 6 months ago because mine did the same but I didnt have ac so sorry no help.

rustbucketrex

Update for anyone checking the archives later.

The problem was more than likely a grounding issue. I did an engine swap in April and installed a powder coated valve cover at that time. There were no issues at that time, but I think that there was not enough grounding to handle the load of running both fans for an extended period of time. I sanded off the coating where the ground wires attach to the valve cover and also replaced the wire that goes from the valve cover to the block(it felt like it might have had a few broken strands in it). I also sanded my other grounding location just to be sure.

It has been 100+ degrees here lately but I have not had anymore smoke rising from the steering column since fixing the grounds. It's nice to have A/C without worrying about catching my car on fire.