Chevy C10 Truck Forums banner

Turn Signals Sometimes Work Most of the Time They Don't?

168 views 4 replies 4 participants last post by  Percey Blakeney  
#1 ·
Have a '66 with a '72 steering column that the that sometimes they do and sometimes they don't when I switch them on. Where should I start my diagnosis investigation; relay? contacts, shorts?

TIA!
Justin
 
#2 ·
For anything intermittent like this you need to start by verifying the basics or you could be running around in circles.

  1. Check all of the wiring (visual, continuity and voltage drop)
  2. Check the connectors. Make sure they aren't lose or corroded.
  3. Check to make sure the ground circuit is good. I've seen people chase their tail for days when it was just a bad ground.
 
#4 · (Edited)
First thing your 66 wiring and the turnsignal itself isn't the same as a 72 model year PERIOD. Apples and Oranges are different and so is the two Colums themselves.
Also yes grounds are usually a problem in 60 year old Rusted vehicles that the metal plays a crucial vital CONNECTION for or to complete its circuit.
 
#5 ·
From a post on another site:


"Because you have a future of dealing with fun stuff like this (obnoxious grounds), the good money is on that it would not be a bad idea to make a ground test cable to store along side your other test equipment.

I'd make it from 10 gauge, which would still be undersized for the alternator and starter, but a quick on and off could still give you clues.

SIDE NOTE:

Many of us use the old battery cable and test light trick to track down problem circuits that drain the battery. That is, after removing the negative cable from the battery, we run a 12 volt light between it and the negative post.

If the light comes on, something is in completed circuit mode, which would drain the battery just sitting.

This can be tested: If the light is off, turn on the park lights, which will create a closed circuit, and the light should come on. If not, you have other issues, like a dead battery, or the park lights not coming on for want of a working fuse or other issue.

SWAPPING the light over to the positive terminal, you can test fully open grounds. You could use the probe to test at various points of a ground termination point (the bolt, the leads connectors, the actual wires).

Just keep in mind, a ground can be just bad enough to stop a high amp item from operating (lights, starter), but a lesser one, like the test light, my still appear to work. So this is a all-or-nothing kind of test.

Backed by a test cable to provide a solid ground for the suspect spots, much can be learned. For example, if it tries to turn over a bit better, the safe money is on a bad ground to the engine."