Tail light malfunction
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Tail light malfunction
1989 f150 5.8 has absolutely no tail or brake lights. Blinkers work, but tail lights don't. Can someone send me a schematic? Also, has anyone thoughts on this? Apparently the fuses are good, but as this is my roommates truck, I don't really know where to start.
Postmaster
Joined: Oct 2003
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From: SoCal
I dont have diagrams for this, but see if the emergency flashers work. If they do try the brake lights again. Sometimes this will clean up dirty contacta in the MFS/multifunction switch.
Sign up for a free account at bbbind.com and you can pull up the diagrams
Sign up for a free account at bbbind.com and you can pull up the diagrams
Postmaster
Joined: Oct 2003
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From: SoCal
Just took a quick look online and stop and hazards are on the same fuse. Fuse 1 and it's a 15 amp
If the cruise control cuts off when you tap the brake the fuse is OK.
The online diagrams dont show it, but i think the hazards and brake lights are wired to the hazard flasher.
If the cruise control cuts off when you tap the brake the fuse is OK.
The online diagrams dont show it, but i think the hazards and brake lights are wired to the hazard flasher.
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I just went out and rechecked her fuses, fuse one is fine. As for the switch, I changed the brake switch itself so it has to be deeper than the switches. As for the cruise, I'd wager it hasn't been connected in twenty years. Tomorrow I'm going to start with the hazard flasher and go out with my multimeter and just start chasing the wiring from the light assembly to the engine and drill blindly hoping to strike oil. I'll definitely be sure toilet you guys know what I find out. Thanks for all the help.
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From: SoCal
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Joined: Apr 2015
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From: Boston, KY
Do the dash lights work? If not, it could be fuse 4 or fuse 17. I went in circles for a long time because I thought I was checking the right fuse, but I wasn't. It never hurts to go through the entire fuse panel occasionally and make sure everything is in order. I wasted a lot of time under the truck looking for shorts before checking all my fuses.
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From: Madison, WI
Fuse assignments are in the owner's manual. As for a diagram, there isn't just one. It's a whole book, the EVTM - Electrical and Vacuum Troubleshooting Manual. Usually available for most model years used on eBay, and worth it's weight in... well... very expensive steak, perhaps.
As for the taillights, also check the front parking lights, and the dash lights as mentioned. Park/tail lights are on a separate circuit from stop/turn/hazard lights, so you may have more than one issue.
As for the taillights, also check the front parking lights, and the dash lights as mentioned. Park/tail lights are on a separate circuit from stop/turn/hazard lights, so you may have more than one issue.