Still need help with dome light on Expedition

On Wed, 03 Jan 2007 20:19:02 -0700, dumbneasy rearranged some electrons to form:

The ceiling switches are the map lights, aren't they?

Does the dome light work when you turn the dash light dimmer all the way up?

On Wed, 03 Jan 2007 20:19:02 -0700, dumbneasy rearranged some electrons to form:

PS, you're more likely to get help if you put the following information in your posts:

1. Year and model of your vehicle

1. Exact nature of the problem ("dome light doesn't work but map lights do, works with dimmer switch but not door switches", etc.)

2. What you've already done to diagnose it ("bulb is OK since it works with dimmer switch", etc.)

Steve here is the answer to your question and I can answer this without looking at a schematic too.. Its your Gem or VSM module depending on the year of your Expedition. The GEM module (Generic Electronic Module) and your CJB (Central Junction Box/interior fuse panel) are connected to one another. If you replace one, you should replace the other one as well. After looking at a diagram of a 2000 Expeditions courtesy lamps, I see that the Battery Saver Relay (BSR) supplies power to the GEM, but I am pretty sure that the BSR isnt replacable. I think you have to replace the whole CJB to fix that relay. Also the GEM is responsible for the grounds for the BSR, and the interior lamp relay, thats how it controls them. SO if its a GEM problem, that will only be about $200, but if its a CJB (water intrusion) problem, then you are probably looking at a GEM/CJB combo replacement and you can almost triple the cost due to the labor involved in a CJB replacement. (seen a few of these in the F-150)..

To make this a bit shorter, take it to either the dealer or a very good repair shop. Trust me, you dont want to mess with this at home, unless you are ASE certified?

Ford Tech

Thank you for the replies, Ford Tech and David M!

My Expedition IS a 2001 and the map lights do work manually, as does the dimmer for the console and the door ajar lights. The map lights (nor courtesy lights) do not operate when you roll the dash lights rheostat to the full on position. However, the dash lights are controllable via that rheostat. I suspected a relay being the problem because all these other apps are still working.

Now here is another quirk. This Ford is a former USFS enforcement vehicle. Hence, it was used for patrol and potentially against poachers. The thought occurs to me that the "when-you-open-the-door" lighting may have been disabled on purpose so you could sneak up on the bad guys.

I guess the first thing I need to know is where the GEM box and the relays are located. I may find one missing.

Thank you again, Steve in Montana

have you looked at the connections behind door switch (s) i dissabled the dome light on the drivers side of my truck by removing one wire out of the three or four there , if i wanted the dome light the headlight twist knob was right there.

Ok so here is an updated fact for you. The GEM and CJB are in fact connected to each other. And there is no real way of disconnecting certain lights without either cutting the wires to the lights, unplugging them at the lights, pulling the individual wires out of the connector at the CJB, or disconnecting all six (6) door ajar switches.. However, all but the doing the door ajar switches would produce the lights not working at all. So the only thing they could have done was pull the door ajar switch wires, or remove them from the connector on the gem. If you cant find the door ajar switches disconnected or the wires removed from the connector. Then you are looking at either a GEM replacement, or CJB replacement. These modules are plug and play and have very few if any programmable features to them.. So it had to have been changed with a hardware change, there isnt an option for it in the software (that I am aware of)

Ford Tech

On Sun, 07 Jan 2007 19:16:08 +0000, dumbneasy rearranged some electrons to form:

You *did* check to see that you had a bulb in the scoket, didn't you? I would check the 'simple' things before you go off tearing into GEM modules.

PS, map lights should only come on when you switch them.

I appreciate the help folks, but maybe I'm the one that is confused. First, all my doors, each and every one, lights the door ajar switch when that particular door is ajar. Second, I have two overhead lights. I pesumed these to be dome lights, but they are in fact, map lights -N'es Pas?

Third, every car I've ever owned had a light come on in the top of the compartment when I opened either front door. On some I could even afford a car that had lights in the doors that came on as well. These, I guess, are known as courtesy lights.

No lights come on when I open a front door. That's what I want to fix.

Gee, I hope I made myself clear... And yes, it's still the 2001 Expedition.

Thank you and please re-read my screen name. LOL!

Check to see if the dome light bulb is even there? The maps lights are not dome light. Law enforcement people don't like the attention drawn to them with the dome light coming on at night when a door is opened. So , either the bulb was removed or one wire connected to the back of each door switch was removed , the other wires to the switch are still operating the door ajar warning light.

Ok, if that is the case, check to make sure there are bulbs in all the lights, and look at the socket for all the bulbs and verify the wires arent disconnected.

I believe you are correct. The maplights are usually in the ceiling, but on some vehicles they were actually added to the bottom of the rearview mirror. Also some map lights double as dome lights and have a switch on them that allows them to be turned on manually, automatically (with doors), or they can be set not to turn on period. Do your lights in the overhead console have a switch on them with 3 positions?

Last but not least, you seem to be having real problems with this. I will make it short and sweet. If the door ajar light and sound is operating normally with the doors, then the switches themselves are in tact, as well as the wring for those switches. SO there are two possiblities for your concern.

1. They have removed the bulbs from all the COURTESY lamps
2. They have disconnected the ground wires from all of the Courtesy lamps.

If you cant locate the courtesy lamps yourself, then you NEED to take this to a dealer. It sounds to me like you are in over your head. Take the truck to a technician to fix it, you ARE NOT qualified to do the repair.

Ford Tech

The answer is NO! But I did put a new bulb in. :)

I know I have taken long to respond. :::::There are so many crisises in my life. :) The rheostat works the dash, the lightbulb in the ceiling is brand new. No, the overhead light does not come on when the rheostat is all the way on. The interior courtesy lights (including the one between the map lights that have to be turned on manually) do not work either. The door ajar light only comes on the dash when a door is ajar and I haven't a clue about the GEM or the CBT, or was that a CBJ? I DO know that one of the relays near the fuses is supposed to be for the interior lights. Whether that means courtesy lights or some other lights-I haven't a clue. In the meantime, I will go through my CD manual and see if there's a diagram. 30 years ago I was an electrician so maybe I'll stumble on to something until one of you fine helpers comes up with a real starting point. Either way, at some point, I'll report back.

Thanks!

Ok here we go. If the door ajar light is actuating with all the doors, the GEM (Generic Electronic Module) is fine. It sees that the doors are open. I think what has happened is that the interior lamp relay has been removed from your fuse panel. If its there I would look for a wire pulled from either the light switch or the fuse panel... I dont know what else to tell you, there is a whole list of things they could have done to keep those lights from coming on..

That means its for the courtesy lamps.. The only interior lamps are the courtesy lamps.

Ford Tech

Thank you Ford Tech. When the snow stops and the sun comes out, I shall endeavor to rectify the problem! :)