Author Topic: Headlight and signal problem  (Read 1752 times)

Offline 86chevytrk

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Headlight and signal problem
« on: June 26, 2019, 11:07:31 AM »
Hello, I too have made the grave mistake of reverse hookup of the battery. It burned the ground wire to the support. I replaced and repaired what I’ve found so far. I have variety problems still but my main concern today are the signals. I have power to start, run and drive. But when I turn on the headlights both directional arrows light up. When I signal either way, the opposite arrow stays lit and flashes only once. I replaced the headlight switch in hopes to fix the problem but all I got is a shiny new switch. When the headlights are off the signals work but seem labored. I’m working on a 85 c20 with the 350 gas engine. Please help me fix this problem as my butt is starting to hurt from kicking it. Thank you in advance.

Online bd

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Re: Headlight and signal problem
« Reply #1 on: June 26, 2019, 11:38:48 AM »
Check ALL of the vehicle grounds.  You can find an inventory of their locations near the end of the tech article Vehicle Ground.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline roundhouse

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Re: Headlight and signal problem
« Reply #2 on: July 04, 2019, 09:41:41 AM »
You might want to replace the turn signal switch on the steering wheel

They are cheap and easy to do
Just remember when you pull the old wire out of the column to tie some fishing line to it and pull the fishing  line in and then you can use that pull the new wire back down

And check the brake light switch and make sure it’s working right

You also need to check each light and make sure the bulb and the socket are in good condition with no shorts

The only place the parking lights and turn signals wires can get crossed is in the socket or bulb
They do not connect to each other anywhere

Offline 86chevytrk

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Re: Headlight and signal problem
« Reply #3 on: July 04, 2019, 04:59:04 PM »
I’ve been at it for awhile now and starting to lose my mind. Thanks bd and round, I will update when I find the cause of this ridiculous problem.

Online bd

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Re: Headlight and signal problem
« Reply #4 on: July 04, 2019, 10:18:43 PM »
The proper function of all things electrical hinges on good grounds.  In fact, legendary hauntings can be traced back to poor grounds.  So begin there.  Concentrate your efforts on the dash grounds to cabin sheet metal under the dash and between the firewall and right rear cylinder head.  Also, verify the battery negative to engine block ground connections.  You may benefit from new turn and hazard flashers too.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline 75gmck25

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Re: Headlight and signal problem
« Reply #5 on: July 06, 2019, 06:08:09 AM »
The first ground wire I would check is the one for the instrument panel.  Its a black wire up under the dash on the driver's side.  On my '75 it was connected to a ground post on the parking brake mechanism, but I believe that in later years they added a grounding strip on the firewall up under the dash.

When I made the same mistake with cables, it burned the fusible link that runs straight down from the power junction next to the brake booster.  My "mistake" burned it partially, and then one day when I turned on the headlights it burned completely and I lost all power to the truck.  Not a fun experience while driving down the highway.

Bruce