jim010

Yhe other day I noticed when I turned my headlights on in the evening that it was darker in the car. The lights that illuminate the buttons were out. All these won't illuminate:

steering wheel buttons
climate control buttons and *****
info centre buttons
track control and hazard buttons
auto shifter selector indicator
overhead convertible up down switch
headlight ****

These still illuminate:
window switches
door lock switches
guages (dimmer works here)
radio (dimmer works here)

There is no fuse for illumination, and all fuses look good anyways. Looking at the wiring diagrams, it looks like there is something wrong with the smart junction box itself. If the headlight switch was to blame, then the guages and the radio would not work either I figure.

Ideas? I need help.

05YellowGT

Did you rotate the wheel on the light switch , which dims everything ?

jim010

Dimmer wheel works only on the guages and on the radio buttons. All the others listed do not light up at all.

jim010

No ideas here?

jim010

Soo ... no one has any input into this?

Looks like I have to get a smart Junction Box for a convertible 05 or 06. Engine doesn't matter.

Located a wrecked 06 convertible a little ways from me. I'll be going out sometime this week to try putting it in my car to see if the problem is fixed. If that doesn't work, then I'll try the switch itself, but it is just not possible for it to be the switch, as other buttons do illuminate, and the ones I listed are the only ones to be routed through the junction box.

watchdevil

The same exact thing happened to me on my '08. I accidentally blew a fuse installing aftermarket ambient LED lighting which I tied into the PRND321 indicator illumination. That knocked out the operation of all the same lights you have out. I had to search for the correct fuse and replace it.

With as many fuses as there are in the fuse panel located at the smart junction box, it's easy to miss one thinking you checked them all. You also have to check for fuses that have multiple things on a circuit. Circuit descriptions in the owners manual can also be deceiving.

Just the other day while working on my '10, I popped a fuse while installing an LED strip for additional trunk lighting which also rendered the map lights inoperable. The fuse was not the one listed as courtesy lamps, but rather the one for timed delay and battery saver.

Another note... The door and window switch illumination is not controlled by the headlamp switch or the dimmer control. They go on and off with the ignition key. Anytime the vehicle is in operation they stay on all the time (even in daylight) at a fixed brightness level regulated by resistors inside the switches.

I would certainly check the fuses again. It's going to be on a 5-10 amp circuit as these are all low current LED lights.

watchdevil

The radio and gauge illumination pull current from different circuits. Likely, the dimmer switch provides a resistance for a common ground for all the lights that are controlled by the dimmer. What is missing is the current from the circuit that supplies just the switch lights.

Also worth noting, if the headlamp switch is ever unplugged from the wiring harness, it will cause all the lamps to stay on until the switch is plugged back in again.

jim010

Thanks Watchdevil.

I will double check the fuses again.

Don't remember which fuse it was by any chance?

Cheers

jim010

OK, all the fuses check out as before.

But driving home tonight, my life just got more complicated. The lights would go on and off intermitently - but mostly just staying off.

Could still be the smart junction box, but I also thought the ground might be an issue. Problem is the steering wheel, info center buttons, convertible top button, light switch and HVAC all have separate grounds.

I still need help here!

watchdevil

Well I am reading out of my 2010 owners manual and it is the same exact fuse circuit as the one that blew in my 2008. The #10 fuse which is the right row counting from bottom to top is showing to be a 15 Amp fuse for Switch Illumination. If you have an owners manual, consult it and see if it says the fuse is in the same position for your earlier model. I am almost sure it is.

I went out to my car just now and pulled this #10 fuse with the headlight switch on. I was able to verify again that the lights go OFF for the headlamp switch, info/setup/reset switch, tcs/hazard/trunk switch, steering wheel switches and PRND321 illumination. The gauges, climate controls and audio system backlighting stayed illuminated. On pre-2010 models the climate control panel will go off with the fuse pulled.
The owners manual also shows that the gauge illumination and dash center panel (audio/hvac) is on separate circuits than the switch illumination.

I discovered also that if you pull the fuse and replace it, you will have to turn the headlamp switch off then back on to reactivate the switch illumination.

watchdevil

I caught your post just now after I just posted a new one for you... Yes all the grounds are separate for those switches you listed above.

Read this again which I just posted:

"I discovered also that if you pull the fuse and replace it, you will have to turn the headlamp switch off then back on to reactivate the switch illumination."

Since this happens, it must be controlled by a relay circuit in the smart junction box. Since you are saying that it was working intermittently tonight, then the smart junction box is the likely culprit. I was just hoping for you that it was going to be a simpler fix that was overlooked. However, I was at least able to figure out that this is isolated to a single circuit which has nothing to do with any other circuits.

jim010

Yeah, I was hoping it was an easy fix too.

Replacing the SJB is easy too, or course, but costly.

The help was very much appreciated Watchdevil.

jim010

I found my problem! It was a short. I tracked it down to some wires leading to the auto tranny shifter. Fixed it and its all good now.

watchdevil

Glad u found it and that it was a much simpler fix than the SJB!

cattman77

I have a problem with the exact same lights except my problem is that these lights stay on even when the vehicle is turned off, locked, doors closed and everything. This happened at the same time that my battery went out. I thought a new battery would fix it but it did not. I know absolutely nothing about cars but I am learning.

Any help on this would be greatly appreciated. I am not exactly in a position right now to pay someone to troubleshoot the problem. Thanks in advance!

FordService

Hi cattman77,

Welcome to the forum! My name is Deysha with Ford Service. You should first check the “Lights” section of your owner's manual:

PANEL DIMMER CONTROL
Use to adjust the brightness of the
instrument panel and all applicable
switches in the vehicle during
headlamp and parklamp operation.
Move the control to the full upright
position, past detent, to turn on the
interior lamps.

If not, you should have your dealer look at it. They’re in the best position to advise of any work needed, coverages, etc. Also, remember repairs done at a Ford Dealer come with a 24 months/unlimited miles warranty. I hope this helps.

Deysha

Artyom

Hi Jim
I have a same problem. I check all fuses with voltmeter and they are ok.
Tell us more where there was a problem.
Thank you.

dmhines

Deysha you do realize most people avoid the dealership like the plague once warranty coverage has expired? You know how much they would have charged him to find a bad ground wire?

jim010

Been a while since I have seen this thread.

I had to go through all the wiring I had done. I figured that the problem had to have been wiring that I had done, and I was right. There were 2 wires that were not quite wrapped properly that were touching each other. I did not have a voltmeter to locate the problem, though. I checked everything visually. My problem was the wires that I used to tap into power for my ambient lighting.

FordService

It is still an option many take, dmhines.

Thanks for the update, jim010!

Deysha