I have an 89 F350 and need to replace the fuse for the taillights, parking lights, dash lights. I took the blown ones out a while ago and cant rememeber the fuse number for these spots.

Little help

 

 

How do I go about finding a bad circuit, everytime I put the tailamp fuse in it blows.

 

Start by removing every bulb on the circuit and then see if the fuse still blows. If it doesn't, then you probably have a bad bulb or socket. If the fuse blows, you have a wiring problem between the lights and the fuse panel. You can insert a two lead light or tester in place of the fuse. The light will glow until you remove the problem. Handy for wiggle tests, the light will blink when you get close to problem if you wiggle the harnesses.

Good Luck!

 

CSRC
I removed the bulbs from the tailights, I had a blown bulb on the upper left side. I put a new bulb in and connected all the bulbs back, but the ligths still do not work. The only good thing is that the fuse is not blowing, would this mean I have a bad socket?
Thanks

 

Sockets can be a real pain, they get dirty or corroded and don't work right. Try your bulbs one at a time to narrow the problem down. There is a remote chance that you may have cooked a fuse link at the starter solenoid, but it is more likely that either the sockets or the light switch is tired. Are your dash lights working
now?

Todd.

 

No the dash lights are still not working, should i replace that one socket where the bulb was burnt out???

 

When I turn my lights on and the fuse that is for the tailights, dash lights and license plate light blows would this mean I have a short in the rear wiring harness. Any help here would be appreciated.

 

Come on help me out here before I lose all of my hair

 

I'm afrain that you are involved in a a process by elimination trouble-shoot.

You mentioned all those lights.
They can be in the same circuit unless Ford changed and did ithat way.

I haven't ben following along with this thread ,but I'll check back now.

 

Should I be checking every single bulb in the back one by one???

 

Here is just an idea, pull your switch and make sure it isn't cooked. If you were blowing fuses, you might have cooked the switch. When my switch went, only the headlights were affected.

Just an idea.

 

Checking bulb by bulb.?
Not if you are blowing fuses.

You should be checking the wires that power the bulbs for going directly to ground.
That's what blows a fuse.
You need to isolate the short.

Look for a connector to unplug to the back lighting system.

Do you have a multi-meter to check continuity in the systems ?

 

I replaced the headlight switch because it was fried awhile ago but this problem just recently happened. I do not have a multi-meter, but I did unplug the harness in the back of the truck to look for any corrosion looks pretty clean though. Should I disconnect each wire, not really sure what I am supposed to be looking for here. Electrical is not my game!!!!
Thanks for the replies

 

Try and think of this as an automatic sprinkler system for your yard.

You have all these zones that are controlled from one or 2 places.

You have to make sure each zone doesn't have a problem.

In this situation everything comes back to the headlight switch when you pull the switch.

You have the running lights (Rear & Front) system
The headlight system
The courtesy light system.

You have stated that fuse for the tailight blows everytime you pull the ****...Right?

The wires to both tail-lights has a connector down behind the left hand tail-light.
Disconnect that connector & put a fuse in.
If it blows the short is between the switch and that connector.
Now get under the truck and inspect the wire all the way to the firewall for a bare wire or what might look a spot where the wire is shorting out.

If the fuse doesn't blow when this connector is disconnected the problem is between the connection & the Tail-lights.

Try this and get back.
We will narrow it down to where it is happening.