Trouble Shooting Turn Signals

Xavier · #1 (**permalink**) 07-18-2009, 08:33 PM

My turn signals have been working fine, then all the sudden they stop working. I notice the fuse (15a) has blown, replaced the fuse, blows again within first moments of the turn signal working.

So I know there is a short; what is the quickest way of finding out where? Can anyone help with some tips on how to trouble shoot this quickly, finding out in proximity to where the problem lies?

Thanks.

strictlypersonl · #2 (**permalink**) 07-19-2009, 05:27 AM

I've got one of these (saves a lot of fuses), but if your circuit has intermediate connections, disconnect them in turn, starting at the bulbs and moving up to the switch. When the fuse doesn't blow, you've isolated the area with the short.

Tommy · #3 (**permalink**) 07-19-2009, 06:56 AM

If the fuse blows only when the left (or right) side is used, then focus on that side of the chassis. If it blows when either side is used, focus on the common wiring used by both sides (e.g., signal switch, flasher).

Xavier · #4 (**permalink**) 07-19-2009, 01:09 PM

So basically, if it happens all the time, it can be the flasher or common wiring, switch or the elctrical in the steering harness. I remember someone saying IDIT had problems with the electrical internally within the steering column - can anyone confirm? I will start there first.

If it does not happen all the time, disconnect all 4 corners, reconnect one at a time until the fuse blows - there is my trouble spot. Correct?

Thanks for the replys...

PANAVIA · #5 (**permalink**) 07-19-2009, 02:54 PM

Sometimes we have had problems with the hub-sub assembly with the turn signal switches and them arching.

Tommy · #6 (**permalink**) 07-19-2009, 04:01 PM

Quote:

Originally Posted by Xavier

So basically, if it happens all the time, it can be the flasher or common wiring, switch or the elctrical in the steering harness. I remember someone saying IDIT had problems with the electrical internally within the steering column - can anyone confirm? I will start there first.

If it does not happen all the time, disconnect all 4 corners, reconnect one at a time until the fuse blows - there is my trouble spot. Correct?

Thanks for the replys...

That's how I'd approach it.

Xavier · #7 (**permalink**) 07-19-2009, 05:56 PM

Thanks Tommy.

autobody prof. · #8 (**permalink**) 07-19-2009, 06:34 PM

A fuse blowing instantly is a direct short to ground. Disconnecting the light at the socket will not help because you have a fiber glass car. A direct short to ground involves metal. Steering column, frame, rearend, something that the wiring has rubbed against and is touching bare metal. Use a DVOM and run a continuity check of each hot lead from the turn signals to the circuit board. Look for very high resistance or no resistance at all.

Michael C Henry · #9 (**permalink**) 07-24-2009, 05:11 PM

Remove each bulb and examine carefully. I've had the fillament break and fall against the other circuit causeing a short inside the bulb. I'm referring to 1157 bulbs, dual fillament bulbs tail/turn front marker/turn. Tail lights on large trucks and trailers on wash board and pot holed streets.

Xavier · #10 (**permalink**) 07-24-2009, 06:04 PM

Mike H -

Great suggestion - I have not heard of that one. Yet another reason to switch to LEDs. I start tomorrow on the diagnosis. Not a moment too late!

Thanks.

rustyBob · #11 (**permalink**) 07-25-2009, 05:16 PM

I hookeed my car trailer to my truck one time and lost turn/brake lights and blew the fuse.......put in new fuse ,it blew........new flasher with another new fuse .......problem solved.......

Xavier · #12 (**permalink**) 07-26-2009, 08:44 AM

Well I did a lot of testing, once the I disconnect the stearing harness and put 12 volts directly to the wires for the turn signals they flash with no problem. Left and right hand side. Once I connect the steering column harness, they blow. I think the easiest way to tell if its a flasher (someone tell me I am wrong) is to use the hazard lights. Becuase the hazard lights go off another flasher, if the fuse still blows then it cannot be a flasher. I fthe fuse only blows when using signals, but does not blow when using hazards -- then it could be the flasher.

Also, a problem I had after my car got painted, my horn does not work. Again, I bypassed the sterring column harness, went direct to-ground from the electrical connection to the harness (works through ground by the way) and the horn works too.

So now the question is - can I take apart an IDIDIT column myself of am I getting over my head? Or should I say, is this going to be one of those things that takes me 3 weeks to do and I am going to wish I just paid someone $100 to rebuild it. Anyone take a part and IDIT column?