79 lighting issues

Reply Subscribe

Thread Tools

Search this Thread

Oct 17, 2015 | 10:12 PM

blk450er

Thread Starter

Senior User

Joined: Aug 2015

Posts: 227

Likes: 2

79 lighting issues

Still going through my trucks minor issues to be road worthy after getting it. The next delima I'm trying to diagnose is the lights. The headlights work as well as all 4 side marker lights. In the front I have no parking lights but the blinkers work, the right front blinker is weak. In the rear I have turn signals but no running lights. Also no brake lights. I cleaned up all the grounds and checked the fuses. I have a bad fuse but it's not related to lights; heater I believe. I'm not an electrical guru so any help in the right direction to get started is awesome. Is it possible the plugs are bad where the wires hook into the plugs where the bulbs insert?

Oct 17, 2015 | 10:40 PM

HIO Silver

Fleet Owner

Joined: Dec 2009

Posts: 20,678

Likes: 83

From: NorCal

Side markers are usually just dirty contacts since they live in the wheel well. Bulbs can also lose contact in their sockets. Clean them all, verify ground, and power, and apply dielectric grease. Reassemble then test.

You do have a multimeter, right? For the electrical beginners, even Harbor Freight's low-buck $7 meter will get you by. I've used it on multi-million dollar homes... it works fine on our trucks. Get one... the electrical systems on these trucks typically need a dose of attention.. but not as much as a Lucas or early 80s Bosch. If you wanna be pro, then get a Power Probe. http://www.powerprobe.com/