Turn Signals Frying

[azbruin]

I originally installed the turn signals on the donor switch - They worked fine but I didn't like the look and feel so I bought a Russ Thompson unit which looks 1000% better. I moved the wires from the Ford switch directly to the Thompson one and immediately started blowing fuses. I finally put a 30 Amp in to test and while it didn't blow, the wires started to heat up from the flasher solder and into the new switch. I took apart the switch and can't see a short. I don't have any lights hooked up, just a meter and I am getting flash. I've got the hazards hooked up and they share the indicators and the lamps.

Is there anything in the Mustang switch that I needed to take care of when wiring the Thompson switch? Russ has been great but he's like me, a wiring neophyte.

I purchesed diodes but when I got home, they were 250 mA and I don't think that is big enough to carry the load. Could feedback through the indicators be a factor here?

[emac]

I had a similar problem. Take the steering wheel and hub off and see if it works ok without the steering wheel. If it does then check the Russ Thompson unit. It will have two small tabs (facing the steering hub) that may be rubbing and grounding on the steeering wheel hub. If that is the problem, then gently bend them, so they arent making contact.

That is what was wrong with mine. It took me two turn switches, bunches of fuses, a relay, and several calls to Russ to figure it out. Hope that helps.

ernest

[SStrong]

I wasn't getting any power to my signal lights from the RT turn signal unit. Using a jumper to the light feeds the signals worked. Yesterday I disassembled my Russ Thompson unit. Two of the wires had no continuity. I pulled the ends and they came right out of the insulation (broken 1/4" from the end of the insulation). I un-soldered and replaced the two wires, and the unit works perfectly. It's possible I pulled them out (I tried to be very careful not to). I put WeatherPak connectors on the wires to make assembly and disassembly easier. The RT unit looks good and is very nicely made, and this fix was pretty easy. This build would be no fun without having to work out solutions to problems.

[skullandbones]

SStrong,

I agree with you about the problem solving thing. But it feels a lot worse when you are on the "unsolved" side of the problem than after you have it solved. I've always felt I could eventually figure out a way to "fix it" but it sure is frustrating sometimes getting there. Oh well, if it was so easy there would be FFRs all over the place! See ya. WEK.

Note: the reason I chimed in is that I have no turn signals right now but have everything else. So I thought I might get a hint if it is the same sort of thing as azbruin's issue.

[azbruin]

Thanks ernest, I already tried that and talked to Russ about it first. He said he had one similar case - probably yours. Didn't solve mine.

Steve

[azbruin]

I'm thinking mine might be the same problem - just shorted rather than broken. I cut off the wire wrap on the outside of the unit and found a bare spot on one wire - possibly melt. How did you get at the connection? I took the outside ring off and could see the wires through a small gap but the back did not want to separate. There are two small rivets that i could possibly drill out but I think it should come apart from the back.

Just following the heat buildup tells me there should be a short in the vicinity. The heat build up is right or left signal but not in the middle position.

[SStrong]

You have to separate the two sides of the assembly after taking off the flat split ring. Mine came off fairly easily. Putting it back together is a pain. The spring seemed to sit at a 90 to the piece (that was how it sat when it came apart), but it lies flat against one of the pieces. It was 104 when I was working on mine, hard to work with sweat in your eyes. If you have a voltmeter, check continuity between the common lead and the right and left leads before disassembly, might save you taking it apart. When I checked mine I got nothing. In your case, you should get no reading on the ohm scale when the lever is in the neutral position. If there is a short, it will read 0 ohms. When shifting to left or right you should get a reading if it is working properly. Hope you have good luck fixing it. I'll follow your post.
Steve S

[SStrong]

Also, if you read a short, it would be easier to remove the black jacket, cut and replace wires, and re-wrap instead of disassembly.

[azbruin]

I'm pretty sure the short is inside the unit on the forward side of the sliding contacts. I have already cut the jacket down to where I can get at it from the outside. I also removed the split ring (got it back on too with some difficulty. I think I need to remove the next piece to expose the solders but I can't see how it is attached (already took out the set screw).

I've had the same temp issues. We're in our humd season and I'm soaking after five minutes. The glasses get drips on them constantly and it's hard to see anything. In July, It was a 115 in my garage but I was more comfortable than the last couple of days in the low 100's.

[azbruin]

I have to admit that Russ and his turn signal unit are vindicated. I Disassembled it to the point where I could at least see the wire connections and they were good. I put everything back together and then disconnected all my wiring from the unit. I just reconnected a couple of lamps and voila! no heat and and good flash. I'll start to put the wiring back one strand at a time until I find the culprit short.

I think Steve S and Skull and bones comments are right on. While these kinds of problems can be very frustrating, the satisfaction and knowledge gained from finding the solution makes up for the aggravation. And the feeling of accomplishment when I'm cruising down the road will make all these tough weeks fall by the wayside.

[turbonut48]

There is a inexpensive short finder kit to locate the vicinity of the short.

Haywire a 20 amp breaker across the offending circuit. As the breaker cycles, theres an analog meter you trace along the wire bundles. The meter jumps if its between the power source and the short. Once you pass the shorted area it doesnt jump, or jumps a lot less.
I used it to find a shorted aux lamp.

The Nut

[azbruin]

Thanks, I've got this thing isolated to my hazard wiring. There is something going on between the interconnections of either the indicators (I wired mine so the hazard blinks both and the turn blinks the left or right) or the feed from the hazards to the lights themselves. Neither should be an issue with the hazard switch open. I put one diode in the turn indicator circuit from the switch and I was still getting heat up right at the diode.

I don't have the original Mustang unit that had a switch that only allowed one or the other to work.