Electrical Issues, turn signal switch?

[Bowtiek10]

The story goes:

1985 K10 Intermittent Wipers, turn signal switch issues

Part 1:

My wipers started to act funny. First the intermittent wipers acted up, then finally one day while driving back home late at night, my lights started to dim out. I turned on my wipers just to mess with things, and sure enough the lights brightened back up. Additionally, I have a battery voltage reading on my FiTech readout that said it went all the way down to 11.5 volts then once I messed with the switch turning the wipers on, back up to 13.5+.

Part 2:

Since the wiper issue was intermittent, I decided I would wait for it to worsen before addressing it directly. I bypassed the intermittent module just for testing, but resulted in no change. Also, must mention here that this is NOT FACTORY WIRING. I installed a painless kit about two years back. Additionally, removing the fuse still allows for the wipers to function. wtf?

Part 3:

Wipers now act out of control with any input to the switch. Doesn't matter, they act out for a good 2 minutes. FiTech readout says <12v before turning on switch, after turning on switch 13.5+ as previously mentioned. Unplugged both connectors to wiper motor. No loss in voltage from here, however not sure if due to intermittent or not.

Part 4:

Due to this being a project truck, I finally finished up my 7 pin/4 pin trailer wiring. From here, turn signal fuse burns out, along with headlight fuse. Did some side-of-road diagnosis while unplugging tail wiring connector and replacing fuse with no luck. I'm really thinking this is pointing to my turn signal switch.

TL/DR: Weird voltage spikes and blown fuses associated with turn signal, headlight, and wiper blown fuses. Diagnosis so far points me towards turn signal switch

Overall would love to hear any help or experience y'all can come back with. Its been frustrating, and just now starting to diagnose it. As a young guy, I'd like to hear it first from some with experience.

Thanks

 

[Gibby56]

I’ve recently had an electrical gremlin that was similar. Constant blown fuses on multiple circuits, weird voltage readings, etc. it ended up being the +12v from a stereo a previous owner installed was cut and shoved under the carpet. Under certain conditions it would make contact with the floor and in result make all the grounds to the body hot. All my issues went away after i removed it.

So maybe you have an old + making contact somewhere? Could definitely be a short in the wiper switch though.

 

[6872xtc]

So the turn signal switch shouldn't have anything to do with the headlights. I would guess that the problem with the headlights is a problem that is separate from the wipers. And they should be separate from the turn signals as well.

In an '85, the turn signal switch is not connected to the wiper switch electrically, so unless something is wired incorrectly, they shouldn't interact with each other, except for the mechanical link that they have inside the column.

As far as the wipers acting odd, that could be the wiper switch, but also I have had a wiper motor do odd things.

I'm not sure what to tell you that is helpful in diagnosing all of this, unfortunately. But I would say that you probably shouldn't assume that the problems are 100% connected. (Just saying, not accusing you of that)
There are probably a couple of problems, or even more that you will have to weed out. The power remaining on the wiper system with the fuse pulled out, seems to be a red flag that the wiring harness isn't done correctly. I assume that you didn't install it, but bought the truck with it in. Other people will often pass off the problems that they created. Try to find what is wrong there, but also check for wires that are rubbing somewhere and causing a partial short.