Turn signal issues

[gavone]

Recently purchased an 85 C20 with a 305,Turn signals worked fine for a couple weeks then I went through two flasher relays in 10 days.Since I purchased the truck the left turn signal would come on,not blink,everytime you apply the brakes.This weekend I will go through and make sure everything is grounded correctly,just looking for any more suggestions.THanks

 

[Ricko1966]

I suspect the turn signal switch itself.

 

[gavone]

the left turn signal wire is spliced into a yellow wire in the wiring harness that goes into the cluster

 

[Terry Wilkerson]

That spliced wire going to dash probably goes to the dash left turn light indicator.

 

[Jgonick]

the left turn signal wire is spliced into a yellow wire in the wiring harness that goes into the cluster

????
yellow (YEL-237) going into dash cluster is seatbelt indicator. nothing to do with turn signal

yellow (YEL-18 ) coming from turn signal switch should run to a bulkhead then to the left tail light.

I suspect the turn signal switch itself.

I agree..

 

[RustyPile]

It doesn't matter what wire is spliced into another.. Doing so is never recommended for repairing a faulty light circuit.. Undo the splice and start over with diagnosing the problem..

For starters, Front turn signals are totally separate from the rear.. Rear turn signals also serve as brake lights, while the front turn signals serve only as such.. The turn signal interior indicator lights are joined to the front turn signal lights. Pertaining to indicator and front, if one works and the other doesn't (same side), this usually indicates a burned out bulb.

 

[Jgonick]

Information to help you

Wiring diagram link

Video explaining brake light turn signal

attachment- don't know if it is needed, but it might help you start with the wire diagram
just a part of the wire diagram that is labeled.

My bet is it is a bad turn signal switch. unless someone spliced wires.

 

[Bextreme04]

Recently purchased an 85 C20 with a 305,Turn signals worked fine for a couple weeks then I went through two flasher relays in 10 days.Since I purchased the truck the left turn signal would come on,not blink,everytime you apply the brakes.This weekend I will go through and make sure everything is grounded correctly,just looking for any more suggestions.THanks

Start simple and don't get yourself going down a rabbit hole. Check all bulbs first. Then check all grounds by actually verifying continuity to ground from the terminal itself. Every single square I have ever owned has had issues with the ground wire connection at the bulb socket itself. It will look connected, but not have good continuity.

 

[gavone]

should I replace the lever too, or just the switch.Now I have no turn signals at all, nothing comes on when I hit the lever, at least before they would illuminate ,now nothing.

 

[Goldie Driver]

should I replace the lever too, or just the switch.Now I have no turn signals at all, nothing comes on when I hit the lever, at least before they would illuminate ,now nothing.

I wonder if the switch connector has come loose - worth a quick check. Long black connector on the side of the column. To answer your question about the lever, probably not. If you have cruise there is a wire running down through the column you would have to work with and if no cruise it is either a chrome lever or a black & chrome wiper switch "operator" with the wiper switch in the column for more fun.

Not sure on the year break for column wipers.