Tail Lights Do Not Work! I'm Stumped!
Fleet Owner
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
You may want to check or run a wire from the NEG post of the battery to the frame.
The frame is insulated from the body by rubber so if you do not have a wire (10GA) running to the frame from the battery neg post it may only be a grounded intermittently.
The frame is insulated from the body by rubber so if you do not have a wire (10GA) running to the frame from the battery neg post it may only be a grounded intermittently.
Thread Starter
|
New User
Joined: Oct 2018
Posts: 8
Likes: 0
Ok sounds like a plan. When I get home I'll run a wire to the frame of the truck and see how that goes. What if I literally ran a wire around the truck from the battery to the harness? Would this give the same effect while I'm trying to diagnose the problem?
Thread Starter
|
New User
Joined: Oct 2018
Posts: 8
Likes: 0
Welp, I've done what subford recommended to no avail. All lights still work aside from the brake lights. I've checked just about everything in the system that could be a problem and I'm honestly at a loss. The only possible (not really) thing it could be are the bulbs, which still both contain two undamaged filaments. I don't know why this would be the problem, but it's the only thing that I can think of at this point.
Fleet Owner
Joined: Jul 2006
Posts: 20,391
Likes: 850
From: Mi'kma'ki
Welp, I've done what subford recommended to no avail. All lights still work aside from the brake lights. I've checked just about everything in the system that could be a problem and I'm honestly at a loss. The only possible (not really) thing it could be are the bulbs, which still both contain two undamaged filaments. I don't know why this would be the problem, but it's the only thing that I can think of at this point.
Fleet Owner
Joined: May 2009
Posts: 21,437
Likes: 76
From: Gilbert, PA
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Thread Starter
|
New User
Joined: Oct 2018
Posts: 8
Likes: 0
Thanks for the help everyone, in response to @FORDF250HDXLTordf250hdxlt, I had already touched up the ground at the back of the truck and ensured the connector was nice and clean. The problem DID turn out to be that "ground" though. I tested it on a multi meter (I do have one Diesel_Brad btw) and there was resistance even on the bare metal I had ground down. So I said ok, that's probably my problem. There was a ground wire that runs with the harness to the front of the truck aside from this wire so I decided to give it a try without that cable connected. It works now. What I don't understand is how this problem all of a sudden sprung up. and if my frame really isn't grounded anymore, will that short any other components? I only bought this truck about 3 weeks ago and I've only owned cars so I'm pretty new to this.
Elder User
Joined: Sep 2018
Posts: 735
Likes: 8
From: NC
The easiest way to make sure every thing is grounded is to ground it yourself. ground cab to frame and bed to frame then ground from battery to frame. I chased grounding problems all over a Chevy I had. I finally bonded everything together and the issues went away. Corrosion takes many forms,often caused by dissimilar metals being in contact with each other.
Lead Driver
Joined: Oct 2016
Posts: 6,185
Likes: 633
From: Houston/Sugar Land
Thread
Thread Starter
Forum
Replies
Last Post
mofoco1
1973 - 1979 F-100 & Larger F-Series Trucks
2
Jul 14, 2016 08:02 AM
jhaas63
1948 - 1956 F1, F100 & Larger F-Series Trucks
3
Sep 22, 2013 05:24 PM