I'm trying to retrofit a set of OEM foglamps to my 04 MC. So far so good, but I got to a point where I need to remove the Fuse Holder III block to re-pin a harness which lies under it (per the instructions). I was able to unscrew/unplug everything except for the front-most wire harness in the front-left part of the panel (a cluster of colored wires in a black harness). Rather than risk breaking it off, I thought I'd ask first:
Does anyone know how to get this off?
Is there a latch mechanism I'm missing or is it just super stubborn?
Or am I misreading the manual?

Thanks in advance!

 

Are you talking about the harness/wires on top? If so, yes, I know how to do that - just did it over the weekend. In the middle of the left side of the harness you should see a small clip - push it in until it disengages. If you can't do it with your fingers a small screwdriver should work. Now you should be able to pull out the harness. Make sure to pull up firmly holding the harness itself NOT the wires so that you don't pull any out. It's a snug fit so it may take some effort, but as long as you don't pull on the wires and the clip is disengaged it will come out.

 

Thanks for the info! I'll give it a shot-

 

Just did this a few weeks ago too. just be 100% sure your pins are all the way in and its a really easy and fool proof install.

 

One other thing, make sure you leave enough slack to route the wire once in the vehicle to the BC1 behind the radio and glovebox. We found it's just reachable without having to use the extra splice that came with the wiring harness.

 

So I got the harness out but then realized that it wasn't the end of my troubles. I can't seem to get enough info from the manual to find out how to get undernieth/remove Fuse Holder III. After removing the 3 screws (2 black and 1 silver) as well as the wire harness, I still cant seem to get things lifted up far enough to get under it to do the necessary re-wiring (assuming I need to do it from the other side).
Do I need to remove the battery&housing or the air intake to get more slack on the wires?
I also saw that the top piece might separate from the bottom piece but thought I'd ask the pros before I get in over my head. Any help would be greatly appreciated-

Thanks in advance!

Also, any opinions as to the best way to run the wires through the engine compartment and through the firewall to the interior?

J

 

Take the box with screws and harness undone, do no lift it, but rather rotate it so the part closest the passenger compartment is lowered, this will leave you wit a plastic cap on the bottom of the box, it wil slide up (takes some wiggling but no pinching) after that is removed the harnesses will be exposed. They might be alittle embarassed at this point and ask to be covered up again

Remove each one you need to add the pins to, and "unlock it" with a small screwdriver to pull back the nessacary plastic tabs (white one is MOST fragile) the insert pin until it clicks (you'll see the tab "lock: than re"lcok" the plastic harness adaptors.

There is a gromit behind the brake fluid resivor we used for this install, just took a hangar and pushed through(small so you may need a flash light and spend some time looking to find it)s.

 

You all are the mangs, really.

Thanks so much. I'll hopefully get a chance to try it this weekend.

Best,

J

 

Motor,

I took a couple of pictures and sent a reply to him as well. We'll get him through it yet.

 

It's been over a year since I did mine but that was my recollection of it as well. The front of the fuse box can be tilted up to a good angle. The rear of the box won't lift because the harnesses entering there hold it down. I did have a terrible time taking off the bottom cover and I must have missed trying to slide it up.

 

OK. So I'm almost done but of course there's one last gotcha, and that is the base module on the right side. What's the best way to get at this? Other than that, everything else is done (I believe). Thanks everybody .

 

Pull the plastic, undo the top plugs unbolt pull the bottom plugs; I lnow much easier said than done.

 

Or are you asking how to route the harness and pull the trim to access the module?

 

I think he's referring to the trim that covers the BC1.

If he hasn't already, it would be helpful if he takes the glove box out up top to help route the harness.

The trim pops out but we also had to pull up the weather stripping on the bottom of the door frame to get the trim to pop out some. We popped out about the first 4 which was enough to get to the BC1.

 

Yup. I'm wrestling a bit with the kick panel. I've got the wires run, but its now a question of getting the kick panel off and pugging the wires in to the harnesses. Any suggestions for getting the rivets out? I'm gonna give it another go after work.

Thanks everyone-

J

 

Do you have a cabrio? I have an '06 cabrio, and the kick panel has 3 exposed fasteners (expanding rivets) towards the rear of the piece. I think the hardtop does not have these fasteners.

I've taken off the kick panels off on both sides of the car (on the right for the fogs and on the left for a different project). Of the six total fasteners, I only got one off cleanly. The others were all very firmly stuck and I could not pull them out without damaging the fastener. I simply obtained replacements from the dealer (part# 51470390017). I don't remember the price but I think they were around $2 each. Actually I drove around for months without the fasteners before I got around to getting the replacements.

 

It was a fight yesterday, but I got one of the pins to pop. When working with the others, I was a bit afraid of bending the plastic too much.
But I take it I'm just gonna have to get medieval on it?

 

The rivets inside the panel should be the same between hardtop and cabrio. Yes, you can just pull harder, or stick a screwdriver into the gap and pry it directly away from the door sill. You can also try pulling the entire piece either towards the front or back of the car (I forget which direction). The rivets go into slots and they come off easier if you are pulling towards one direction.

 

Well as it stands now, everything is wired up. I need to splice in some extra wire to get to BC1 module with enough slack to get the kick panel back on. However, I've got bigger issues apparently. My fogs (and switch LED) are on full-time; even with the ignition off. The only way to get them to turn off is to disconnect the battery, which is doable, for now. I've got an appointment at the dealer in a couple days for some programming things and I could have them suss it out at their hourly rate, but of course, that's not why I started this project ; ) Any ideas? Thanks for all the help thus far!

Easy,

J

 

The fog lights are essentially connected directly to the battery, through a relay (and fuse). Either the relay is stuck or the control line to the relay is high all the time. The relay control line is a brown/green wire that runs from the BC1 to the fuse box. At the fuse box, the wire is at connector X4010 pin 6. At the BC1, it is at connector X254 pin 40. The brown/green wire should be high (12V) to turn on the fogs, and low otherwise. If the dealer has not yet programmed the BC1, I think the brown/green wire should be low all the time.

I suggest you remove the brown/green wire from the connector at the BC1 and check its voltage. If it is constantly high (12V) whether the ignition is on or off, the wire may be shorting out with a 12V source somewhere along its length. If it is not high, see if the fogs are still on.

I'll stop here for now. I don't want to start listing many possible scenarios that may or may not apply to you. If you could report results up to this point, it will determine the next move.

 

A disappointing finish. I had my car in for service today and in addition to the coding for the rear fogs, I had them troubleshoot/finish the wiring for the fogs . It turned out the problem was the wire running between the fuse box and BCM 1. Right on, RKW.

I was close, so it only cost me an hour and a half of shop time (1hr diagnostic, .5 hour to fix). At least now I can put it on them if something goes wrong down the road.

I guess that's the price of education. At least I know my car better .

Thanks so much guys for all your help with this-



J

 

Does anyone know the name of the type of connector that hooks up to the OEM FOGS or where they might be available? I picked up a used set of fogs here on NAM, plan to wire them in with my PIAA 540's but don't have the actual plugs that go into the lights. Thanks.

 

Mine came as part of the OEM foglight retrofit kit. One of the pieces in the kit was a pre-fab wiring assembly with the connectors already attached. I wonder if you called the parts department at your dealership if they'd be able to order you replacement connectors or (less ideal) the whole wiring assembly from the kit.

 

Thanks, tho I was hoping to avoid that.