i have a 2001 ford f150 supercrew and the dashlights/ ac control lights etc keep blowing the fuse. I tryed changing the headlight switch with no luck. I have no power coming out of the swich to the wire that controls the dashlights.(light blue/red stripe wire)

 

Few questions.

Did you replace any LEDs in the switches on the door ( green to blue change out ) ?

Did you install an aftermarket headunit ?

Have you tried changing the position of the instrument panel dimmer, prior to changing a fuse ?

When does it blow CJB ( Central Junction box / cab fuse panel ) Fuse #18, as soon as you turn on the parking lamps, only in the head position, etc ?

 

it blows as soon as i go to parking lights. head unit do u mean radio, if so i have an aftermarket radio that has been in the vehicle for about a year. and yes it blows #18 5amp fuse. tryed changing dimmer switch location no luck, no LED replacement

 

Try unplugging the upgrade radio, replace the fuse, and test again.

That is the one thing that is not from the factory, and best to test with that out 1st.

The other is did you add any gauges or other lights that run off the dash lights ?

 

unplugged the radio and still the same thing, I have not added any gauges or lights to the dash light circuit

 

If you are up to it, time to pull parts off, and test.

You already unplugged the radio harness connector in the dash, so that was a big unknown confirmed as not the issue. There is nothing else that was added to the truck aside from the radio head unit, so that leaves a problem with the actual truck harness / items.

The easy one might be the connector for the door switch illumination, if you want to try that alone, or

The list I think ( and this is all me, nothing official ) I would un-plug, and retest with :

Connector under the steering wheel column
- C234 is a 6 pin ( 2 rows of 3 ) brown connector for the airbag sliding contact ( not the airbag itself, might see it called the clock spring ) for the control illumination.

Instrument cluster illumination connector
-C237 is a 22 pin ( 2 rows of 11 ) black connector fo the instrument cluster, behind the cluster

Connector for the door switch illumination
C206 is a 16 pin ( 4 rows of 4 pins ) by the fuel inertia switch, passenger side kick panel.

Connector for the function selector switch ( HVAC )
C219 is a 2 pin black connector on the HVAC controls.

4WD mode switch, if 4x4, if 4x2 not an issue.

Ashtray illumination connector

adjustable pedal connector

Overhead console connector

That is everything that is connected to that circuit.

If you mass unplug everything, install the fuse and still have a problem, it is time to start tracing the individual circuits to the connectors that are hanging open.

That is where I am at, unless someone can offer a better idea, which I would be glad to hear.

 

no luck checked by disconnecting all circuits and still have no dash lights

 

I ran a jumper wire on the back of the dimmer side of the headlight switch. Jumped the dark blue white wire to the lightblue/red wire and I have all dashlights. I dont under stand this..

 

If you did disconnect all the above items, you would not have dash lights.

The question is with all the connectors unplugged did it blow a fuse ?

When you put all the connectors back, did you blow a fuse ?

Prior to jumping the dimmer switch, did you check and see if it was rotated all the way down ?

 

the other day the fuse did not blow but I still did not have dashlights, so I ran a jumper wire from the blue/white wire to light blue/red wire and all lights worked. I took the jumper off and disconnected the connectors that you explained and still had no dashlights. The fuse did not blow out either. I have heard from some people that these trucks have a problem with a windshield leak that runs down and drips on the fuse box. This causes alot of goofy problems could that be my problem.

 

Not if you jumper the dimmer switch, and everything works, it is the dimmer switch, not the GEM.

The switch you changed out, was it new or used ?

Did you roll the dimmer all the way up ( to the point the interior courtesy lamps came on ) ?

 

It was a brand new switch that i purchased from auto zone and yes the interior courtesy lights work. Is the switch suppose to send power out of the lightblue /red wire to the dashlights

 

I had no Illum. lights one day, and followed the Hayes manual elec. schematics, with no luck. I found the owners manual, and found illum.dash lights were from fuse 23 under dash - found and replaced the fuse - now have lights. Don't know if this helps or not.

 

tryed fuse #23 and still no luck. thank you

 

The dash lights are controlled by wheel, dim to bright.

If you jumper the dimmer, there is a problem with it.

Still not blowing the fuse ?