06 Exp Dash and climate control lights

[Eric W]

Hello, new owner of an 06 Expedition King Ranch. Previous owner handed off an after market head unit claiming he wasn't sure he plugged the audio for the dvd player in so he thought he'd give me the one he took out..turns out he did a hack job on the wiring harness and cut factory wires. I dont believe that is the cause of this issue however.

When I installed the after market receiver it appeared all was right in the world (ish..) but then I realized I no longer had any illumination on the instrument cluster or the climate controls. Brake lights, map lights, and mirror signals all appear to be fine. Just the instrument cluster and climate controls are dark. I hope it's just a fuse, but no book came with the truck and I am getting mixed signals when looking online. Anyone have any ideas where to start?

I did put the factory head unit back in to make sure it wasn't something wonky with the crazy job he did with the after market harness and the lights didn't come back on.

Please...help!

 

[stamp11127]

Did they work prior to swapping the head unit?

 

[Eric W]

Yes, they did.

 

[stamp11127]

I'll post the wiring diagrams later today when I get on the home computer. If you have a test light or meter check the fuses with the ign key turned to run - engine doesn't need to be running. You should have power on both sides of the fuse. Power on one side means the fuse is blown.

 

[Eric W]

Thank you Stamp!

 

[Eric W]

removing irrelevant information

 

[Eric W]

Fuse 35, 36, and 42 do not seem to light up with the tester on either side of the fuse. I replaced 42 (did not appear blown, but the metal prongs were discolored) and 36 (was blown) but still no dash lights. These fuses also do not light up with the tester still. All other fuses lit up.

All gauges and instrument lights come on fine on the dash, just not the illumination to see at night.

 

[stamp11127]

Here are the two diagrams for the cluster illumination. Unfortunately the brightness is controlled electronically - the pwm listed in the diagram. Check the fuse F1.6 listed on 71-01.

If all of the other lights listed in the diagrams will dim down then the problem may be the wiring for the ground G200 or the splice 19 or Lite Blue/ Red Striped wire to the cluster.

 

[Bedrck47]

In order to see power on fuse #35 your high beams must be on

In order to see power on fuse 36 or 42 you need to place your turn signals on either left or right These two fuses are for the trailer tow connector

 

[Eric W]

Ok, so fuse 6 in the panel and the light blue/red wire in the harness. What if the pin for the light blue/red harness goes to a pin on the aftermarket harness whose wire is connected to nothing? It's just the damndest thing. Factory stereo when I bought it and dash lights. No sound on DVD player. Put in pioneer previous owner gave me that was already wired..boom DVD audio (rear only) but no dash lights. Re-installed factory deck, no dash lights. He cut the harness for the rear DVD and spliced rca cables in and a power lead but I don't see any other splices in the factory harness. The dimmer switch works in that it will turn on the overhead lights when spun all the way "on", is there any chance it's still that switch?

I can fix a computer all day long but this makes me nervous and confused

 

[stamp11127]

Do you know what pulse width modulation & duty cycle are?

Depends if that wire no longer is connected to the cluster. That wire isn't the "old school" hot wire - it is now a digital signal wire. Hopefully he didn't tie into the low speed data bus for other wires.

If it were me I'd pull all the crap wiring the po installed then come back and wire it correctly.

 

[Eric W]

I don't think he did. I believe he only cut the power and audio wires from factory DVD harness (cause the $15 aftermarket adapter would have obviously broken the bank). Spliced it into an rca and the power into power lead on factory head unit harness. I saw no other cut wires.

I am out of town now for a few days on business but weather permitting will be digging back into this mid week.

 

[stamp11127]

What wire color did he use for the power?

 

[Eric W]

I will check once I'm back in town and let you know.

 

[Eric W]

Sorry for the delay. I appreciate the help. I was able to resolve this, it was the headlight/dimmer switch. Looking at the way the previous owner had the stereo wired it looks like he connected the illumination wire to power...bought a new switch on ebay and tore the old one open. Looks pretty bad

 

[Adieu]

Look on the bright side....didnt burn down your truck, just a lightly toasted PCB

Maybe call him ask what other mods he's done?