Turn signals partially functional

[NocturnalEmber]

Hey there everyone,

My remaining issues I have split into three separate threads, with this one focusing on the turn signals.

The past thread got a bit convoluted, but thanks to everyones contributions I was able to solve my main issue (so far), and this thread is focusing on the signals.

Originally, the signals didn't work whatsoever. My fuses in the passengers kick panel were not blown, but they were so oxidized, they had built up a ton of resistance so virtually none of my electronics were working, and those that were, were heating up their respective fuse (dome light) or illuminating their respective warning lights VERY dim (Brake light on cluster).

Changing all of the fuses in that kick panel resolved those issues, as well as partially resolving my turn signal problem.

Now, when I activate my left signal, the signal indicator on the instrument cluster stays solidly illuminated and doesn't flash properly. The right indicator does work as intended (it seems to flash slower than what I'm used to, but that could just be the speed at which the Z flashes its signals.)  

Hazards function properly, as do headlights and high beams.

I have replaced the ignition switch with a Beck Arnley unit, as well as all fusible links with new ones. I also replaced the main ignition relay for good measure. 

I'm leaning towards the switch itself possibly being corroded, but if anyone could give me a basis on which to start I would greatly appreciate it, as combing through the FSM, I see a few potential avenues, but I don't want to put the cart in front of the horse so to speak.

[SteveJ]

As usual, I will start with a flurry of questions.

1. LED or incandescent bulbs?
2. How old are the flasher units?
3. Is the car running during these observations?
4. If the car is running, are you driving or at idle?

The reason for these questions is that old flasher units worked off the principle of a bimetal strip heating up. Since the two metals have different coefficients of expansion, the strip bends as current flows and breaks contact in the circuit. After the circuit is open, the strip cools rapidly and snaps back into place, closing the circuit. From there it's a continuation of wash, rinse, repeat. The hazards could work while the turn signals don't because of many possible reasons

1. The flasher isn't used as much.
2. The switch isn't used as much so it doesn't have corrosion on the contacts
3. Since there are more bulbs (parallel paths) in the hazard circuit, more current is flowing. Note: this especially applies if you have LED bulbs.

[NocturnalEmber]

7 hours ago, SteveJ said:

As usual, I will start with a flurry of questions.

1. LED or incandescent bulbs?
2. How old are the flasher units?
3. Is the car running during these observations?
4. If the car is running, are you driving or at idle?

The reason for these questions is that old flasher units worked off the principle of a bimetal strip heating up. Since the two metals have different coefficients of expansion, the strip bends as current flows and breaks contact in the circuit. After the circuit is open, the strip cools rapidly and snaps back into place, closing the circuit. From there it's a continuation of wash, rinse, repeat. The hazards could work while the turn signals don't because of many possible reasons

1. The flasher isn't used as much.
2. The switch isn't used as much so it doesn't have corrosion on the contacts
3. Since there are more bulbs (parallel paths) in the hazard circuit, more current is flowing. Note: this especially applies if you have LED bulbs.

 

The flurry of questions are always appreciated, Steve!

 

1. Incandescent bulbs

2. Unknown age of the flasher units, presumably factory aged

3. Car is not running during these observations/tests.

4. See #3.

 

Based off of what I have encountered in this car so far, its been untouched (thankfully) on the wiring side of things, and based on how those fuses looked when I pulled them off a few months ago, I think the car literally sat in a garage for quite awhile for oxidation on the fuses like that to set in, though that is just a theory. Same observation when I was looking under the dash at the relays, etc. Nothing looked tampered with, though I realize appearances can be deceiving and I'm not treating that simple visual inspection as a be all end all.

 

I'm wondering if the switches themselves could be the culprit, as the park lights/interior lights can be "persuaded" to come on with some tapping on the headlight stalk when in the on position.

 

[Mark Maras]

I had a 521 pickup that had corrosion on every electrical connection I could see. I disassembled each connection (grounds too), wire-brushed them, and sprayed them with Caig DeOxit. Everything that had previously worked intermittently or was dim, worked like new.

[SteveJ]

See how the turn signals behave with the car at idle. If it's still the same, hold the engine at 2000 RPM and see if it changes.