I just replaced them all with 65W Osram bulbs, on my halogen-equipped '05 MCS with MINI driving lights installed. All was fine for about a half hour of around-town driving. Then I decided to fine tune the aiming on both the headlights and the driving lights once and for all. I got the headlights just right (they were already dead even, just too low--one full turn of the screw on each side did the trick). Then I switched to hi-beam and turned on the driving lights. I've only used the driving lights once before, in the month I've owned the car, because they were aimed too high to be of any use. So I lowered them by gradually tweaking them by their brackets until they were both just right.

Just as I was finishing doing this, the left side hi-beam went out. Switched to lo-beam and the left side lo-beam was out too. All other lights still worked, including the driving lights (only when switched to hi-beam, like they're supposed to). I checked the bulbs, and they're not burnt. Fuses are still good too. Switched driving lights off, left headlight still out. Shut the engine off, did the "follow-me" feature, still out. restarted the car, turned headlights on, still out.

H-E-L-P-!! What is wrong with my car? Does the computer not like the 65W bulbs? Was having the driving lights on with the 65W hi-beams too much load? Is there something that needs to be reset? If so, how do you do it?BTW, the driving lights still have the original 55W bulbs, but I did notice a little rusty moisture at the bottom mounting nuts, where the wires come out, and the wires themselves seem a little loose on the left one, but no matter how I fiddled with the wires, the driving light would not go out and the left headlight would not come on...so, I don't think that's the problem. All the rest of the wiring looks good and intact, as far as I can tell. I have not yet tried putting the old stock bulbs back in, but it doesn't seem likely that will make a difference at this point. Any help from here would be greatly appreciated, as I really don't want to make the trek to the dealer!

 

The 65W bulbs on their own will not overload the headlight circuit. I use the same 65W bulbs on my 06 MCS.

However, I am not sure how your driving lights are wired into the electrical system, specifically through the general module control unit (A1-A). If both driving lights are wired into the left headlight circuit that could create a problem. I assume that the driving lights use their own separate relay but still are controlled through the general module control unit.

The left low beam and left high beam have separate 1.5mm wires going to each bulb so the 65W bulb is no problem for the wire gauge size. From reviewing the electrical wiring diagrams, it appears that the left lights are separate from the right lights but the diagram does not provide any detail on the circuitry internal to the control unit. My guess is that fuse FL8 is used for the left lights and fuse FL12 is used for the right lights. Both are 50A fuses. I would check the 50A fuses FL8 and FL12 again. My guess would be a fuse problem.

In the wiring diagram, I only see one 1.5mm ground wire for both left bulbs (high and low) so that is of concern if that one wire is the ground for the two 65W bulbs plus the two 55W bulbs (driving lights). My hope is that there are multiple ground wires and they just are not shown in the diagram. However, it the ground was a problem and used for all four bulbs, I would expect all four lights not to work which is not the case. So the ground is probably not the issue.

If the driving lights are connected to the left headlight circuit, it seems unusual that the drving lights would still work but the headlights do not work, unless something happened to the headlight fuse or general module control unit.

It does sound like something heated up and failed. If you still find the fuses to be OK, I would check the headlight connector and wires to make sure they still looks good. Follow the wires back from the headlights as far as you can looking for any damage such as discoloration due to heat.

I would also put in the old bulbs just to make sure it is not a bulb problem since it is an easy thing to check. It is easy to get a little finger grease on the bulbs which will cause them to fail when they get hot.

Good Luck.

 

Thank you SOOOOooo much for the thorough and informative circuit insight and advice! I don't yet have any wiring diagrams or repair manual for this car, so I'm at a BAD disadvantage right out of the gate. I only visually inspected the fuses with a flashlight, but I'll take them out and check them with a meter to be sure. Then I'll switch the bulbs back... I did grab hold of the 2 or 3 associated ground points I could find, and they appeared solid and uncorrupted.

 

Your plan sounds good. I believe the headlight fuses are large and look more like a small relay so a meter check is probably best.

 

FOUND AND SOLVED THE PROBLEM.

I called the SA's at Prestige MINI (shameless plug; but they were very helpful over the phone), and after the guy I spoke with conferred with other SA's, the general concensus was that there really was no way it could be anything other than the headlight housing connector, the wiring within the housing--going to the individual bulbs, or the wiring immediately leading up to the connector, given my symptoms and what I've checked so far.

So, I started with the easiest thing first--the connector. I did look at the connector briefly last night, and it looked fine. But on closer inspection, I noticed that the middle female socket on the plug-side looked slightly...I don't know...different. Like the contact was slightly out of line with the other two. This was the one going to the brown wire (which I think is ground, which would explain the symptoms). So then, I craned my head around like Linda Blair and looked up at the male pins in the connector on the headlight housing-side (which I hadn't done last night, BTW), and the middle pin was definitely bent up and out of line with the other two. Bent it back nice and even, straightened the socket connector out best I could with a jewelers screwdriver, added a small drop each of conductive lube to all the contacts (did this for the other headlight too, BTW), and VOILA, problem solved.

This threw me for a loop because I was SURE it had something directly to do with changing the headlight bulbs, or adjusting the driving lights, so that's all I was looking at. But, I believe that the added load on the circuit from having the driving lights on while adjusting them may have caused that connection, which was going to fail eventually, fail right there and then instead. (Remember, this was only the second time I've ever used the driving lights!) Anyway, thanks to those who helped.

 

For the educational discussion:

This threw me for a loop because I was SURE it had something directly to do with changing the headlight bulbs, or adjusting the driving lights, so that's all I was looking at.
When you are sure everything is right and it still doesn't work, something you are sure of is wrong. I keep this hanging over my work bench and computer. I learned its value when I was actually a code cutter.


But, I believe that the added load on the circuit from having the driving lights

Actually the factory (and most others I've installed) driving lights draw their power from a direct tap to the battery terminal feeding the eng' compartment fuse panel and have a sep' fused circuit (you add that in the install), in a sense they run off the extra juice laying around B4 the on board computers. So it is more likely that what ever banging around you did while adjusting the lights, esp' opening and closing the bonnet if you did that, caused the physical dislocation of the bent connection. {fogs on the other hand ARE controlled thru the on board computers et al}

 

Glad you solved the problem and it was a simple problem to fix.