Fix for infamous LBF problem

[Liquidsunshine]

My experience is that 55W ballasts overloaded my E36 wiring and didn't light. Well, one didn't light sometimes and flickered other times. The startup draw is too much. You need a relay and heavier wires from the battery.

I also believe that the LBF function computer gets fried when you run HIDs and this is why error eliminators don't work. I plugged my halogens back in and the LBF message was still there.

[e30azn]

can some one explain what is LBF? and what's the advantage to do this?
Did some research and still can't figure out why or what...

[E36forever]

^Being able to read would help.

Low Beam Fault.

The shunts get out of cal and you will get a LBF all the time. It's annoying to most people even when your low beam bulbs are still good. It's really a silly indicator as anyone should realize at night if they have a bulb out.

[ocyrus411]

just did this fix right now, WOW what a b*itch

couldn't get the white plug apart from the CCM, i was able to slide it like a 1/4 of an inch towards me, but that was as far as it was gonna go, so i basically pulled the wires down as far as i could, cut, splice, done

i'm super happy with my low beams now, and super happy this thread still exists

thanks for the writeup man!!

[KLLKLLKLL]

is that DIY for 95 or 96-99?

I know the wire colors are different from year to year

what s a CCM?

I tried on 1997 e39, colors are different. no luck this time. i tried to find wires on similar locations on white socket, i lost left front fog and right front head light.i re soldered back all. any comments?

[JDStrickland]

This works GREAT! I looked in my Bentley to see what I was doing electrically, and it makes perfect sense.

TIP
I found it helpful to remove the single screw that holds the headlamp switch/duct so I could look into the space behind and see the CCM more easily.

There are four wires, YEL/RED, YEL/GRY, YEL/BLU, & YEL/GRN. The YEL/RED & YEL/GRY wires are the votlage feed for the headlamps (Low Beams) into the Control Check Module, and the YEL/BLU and YEL/GRN are the output of the CCM that physically go out to the headlamps. The CCM knows what the headlamp power demands are supposed to be, and triggers the LOW BEAM FAILURE when the expected load and the actual load are not the same.

What you are doing here is cutting the CCM out of the lighting circuit while retaining all of the other features that the CCM offers. This is not a spooky job by any stretch of the imagination.

The only important thing is to not connect the YEL/RED and YEL/GRY wires together. You can connect the YEL/RED to either the YEL/GRN or YEL/BLU, and vice versa for the YEL/GRY.

To make this easy, cut the wires as stated and ignore the short pigtails remaining from the connector. Connect the YEL/RED to either the YEL/GRN or YEL/BLU, then connect the YEL/GRY to whatever is left.

Now the voltage to the headlamps goes straight from the light switch (via a relay and fuse) to the headlamps, and does not pass through the CCM. Easy schmeasy...

The YEL/GRY wire goes into the CCM on Pin 8, and the YEL/RED wire goes in on Pin 15. The outputs are on Pins 13 & 12 (left and right, respectively).

[Burkemotopros]

Great information. Thanks to all for the input.

[ErikB34]

sorry to bump an old thread, but thanks for the info. lbf after hid install is now gone

[odessa91]

Found another option to fix in different thread w/o disabling CCM, for anyone who is interesting:
http://forums.bimmerforums.com/forum....php?t=1272771

After reading both post and
Based on my recent experience to deal with LBF on my car with HID, the way I fixed it, just replaced CM under dash with good used one.
The original part number:
61351387620, New Part Number: 61358353098
In general e36 carts should not give you LBF if this control module under dash is working properly. Here is a details, with steps to trouble shoot. the issue. I had my HID on my car for over 3 years and did not have any LBF. Recently it started, after checking connection I found loose connection where round plug connected to DEPO headlights, the reason for loose connection - original BMW OEM female pins slightly bigger than DEPO lights male pins. After fixing this connection still get LBF. Plugged original 51W 9006 bulbs directly to car plug, still LBF. Pulled both fuses for low beam and measured amp for each, everything in range about 4.2AMP per bulb. Plugged 60W bulb, still LBF with 5AMP at fuse. Replaced module with used one, and LBF gone, plugged back HID, no LBF.
Just for statistic:
I have original 7.5AMP fuse for each low beam bulb, they never been burned.
When 35W HID start it is about 6 - 6.5AMP, and in less than 30 seconds AMP drops to about 3.7AMP
If you install 55W HID you may need to update fuses to hold spike during HID start-up, do not worry about wire, the way wire design, if it designed for 7.5AMP, it means it should support 7.5AMP 24/7 without overheating.
I think it is 2.5 sq.mm wire (equivalent US Gauge # 14)

[M3flyboy]

Just did the fix...worked like a charm on my 1998 M3, on which I had just installed Umnitza DEPO HIDs, both low and high.

Decided it would be LOTS easier to do the job with the driver's seat removed, which was no big deal - 2 nuts on front rail, 2 bolts on rear rails & 3 electrical connectors to unplug. Didn't even take it out of the car - just slid it onto the rear seat...cannot imagine doing the required body contortions with the seat in the way, even in the rearmost position. I STRONGLY recommend removing the seat.

I also disconnected the positive battery terminal cable, just in case I did something stupid which fooling around under the instrument panel.

The white plug was a big of a hassle to un-plug...took me awhile to realize that I had to slide the outer sleeve back to "unlock" the plug - had to stick a long flathead screwdriver in the little slot and lever the outer sleeve back. As to the nuts that hold the module in place, folks should be advised that these are tubular black plastic & only finger tightened, so it's not a hassle to remove the front one and loosen the rear one...need to push the wiring harnesses out of the way to get good views of these.

THANKS SO MUCH for absolutely clear instructions and pictures...couldn't have done this fix without them.

[burritolover]

Hello,

Just wanted to say thank you! I just did this fix last night. I have been running hid's for six months with the LBF error always on. Was extremely aggravating and and easy as pizza it is gone!

This was an easy fix, I found it most comfortable to sit on the ground outside of the car with my legs under the drivers door. Definitely would be good to do during the day. Even with several flash lights there were many shadows cast by wires and such.

Again Thank You!

[scottz2]

Worked for me as well. I didn't remove the module at all. I left it installed and just cut/spliced the wires as JDStrickland noted above. One thing that may have made it a bit easier for me is auto trans.

[Teradae]

I found a way to fix this.
I ran the cut un-connected ends that come out of the computer (yel/blue and yel/green on my car) to ground.
This fixed the problem completely.

On my 1992, the computer was checking for ground through the headlight bulbs at startup, whether the headlights were on or not, so those leads need to be grounded.

Big thanks to you Gofast, mmaigret's fix didn't work for me either but your grounding addon certainly did. Mine is a Canadian 94 325i.

Very nice to be rid of the annoying lbf warning.

[E36forever]

You guys never had to cut wires to fix the LBF. You also didn't need to buy anything either.

[Teradae]

I'm afraid I did, the module checks for low beam on ignition and I've bypassed the headlights as DRLs so the xenons aren't on all the time. Headlight switch works like it's supposed to now and Ive added white led's in the grill for the DRLs.

[piere1711]

HI mike. i have a question a made this process in one of my bmw e36 and gave me a good results but in my other bmw same model now i had the problem that when i make contact the computer show me low beam failure with not contact the headlights, if you could help me with this I'd appreciate ally thanks. atte piere

[Kasdan]

My car has stock bulbs, all of which work, and I still get the LBF warning. MOst of what I see here applies to those adding HIDs. WHat could my problem be or do I need to just try one of these fixes as well?

[rene88]

hey guys, this thread is phenominal!! just want to see if anyone has any input on my issue. i'm using Depo headlights with angel eyes and 55 watt HID's and one of them stopped working so I went for the quick way out and thought it may have been the bulb but after replacing the whole HID unit itself I came to realize that there is just no power coming to the actual plug that's coming from my car to the headlight (or in this case ballast)... fuses are all ok but after using a voltage reader thats how we realized that its dead. theres just no power at all coming to it. the other one is perfect and before this i never had LBF or anything of the sort (lucky)... anyone have any ideas?

[BMWJNKY]

hey guys, this thread is phenominal!! just want to see if anyone has any input on my issue. i'm using Depo headlights with angel eyes and 55 watt HID's and one of them stopped working so I went for the quick way out and thought it may have been the bulb but after replacing the whole HID unit itself I came to realize that there is just no power coming to the actual plug that's coming from my car to the headlight (or in this case ballast)... fuses are all ok but after using a voltage reader thats how we realized that its dead. theres just no power at all coming to it. the other one is perfect and before this i never had LBF or anything of the sort (lucky)... anyone have any ideas?

Could be a relay problem. Also I have had fuses test good but not make a good connection so it wouldn't hurt to throw new headlight fuses in to see what happens.

[rene88]

good idea, doesn't hurt to double check the fuses... ill give it a shot, thanks!

[GarethC]

Took me 10 minutes as I was already chasing a clutch Pedal squeak! Thanks for the write up.

[zookie]

Bumping up an old thread as my LBF is killing my enjoyment of my HIDs... but this would be a lot easier to follow with pictures... taht don't seem to exist anymore. Can anyone help me out?

[Andres]

Bumping this thread up for future DIYers. Took some pictures to help out since there was a request for them since the OP's are down.

All I needed was post so thanks for that.

This works GREAT! I looked in my Bentley to see what I was doing electrically, and it makes perfect sense.

TIP
I found it helpful to remove the single screw that holds the headlamp switch/duct so I could look into the space behind and see the CCM more easily.

There are four wires, YEL/RED, YEL/GRY, YEL/BLU, & YEL/GRN. The YEL/RED & YEL/GRY wires are the votlage feed for the headlamps (Low Beams) into the Control Check Module, and the YEL/BLU and YEL/GRN are the output of the CCM that physically go out to the headlamps. The CCM knows what the headlamp power demands are supposed to be, and triggers the LOW BEAM FAILURE when the expected load and the actual load are not the same.

What you are doing here is cutting the CCM out of the lighting circuit while retaining all of the other features that the CCM offers. This is not a spooky job by any stretch of the imagination.

The only important thing is to not connect the YEL/RED and YEL/GRY wires together. You can connect the YEL/RED to either the YEL/GRN or YEL/BLU, and vice versa for the YEL/GRY.

To make this easy, cut the wires as stated and ignore the short pigtails remaining from the connector. Connect the YEL/RED to either the YEL/GRN or YEL/BLU, then connect the YEL/GRY to whatever is left.

Now the voltage to the headlamps goes straight from the light switch (via a relay and fuse) to the headlamps, and does not pass through the CCM. Easy schmeasy...

The YEL/GRY wire goes into the CCM on Pin 8, and the YEL/RED wire goes in on Pin 15. The outputs are on Pins 13 & 12 (left and right, respectively).

Pictures are here http://imgur.com/a/eQIw9

[jurrrd]

Hey guys I need some help. I just did this mod and it worked and removed my LBF code but now my car won't start


i need need some help on what I could have possibly messed up... I even tried to reconnect everything the way it was and it still wouldn't work.

Replaced my immobilizer fuses, reset the check control/OBC


im out of ideas.
someone please help!!!!

- - - Updated - - -

Hey guys I need some help. I just did this mod and it worked and removed my LBF code but now my car won't start


i need need some help on what I could have possibly messed up... I even tried to reconnect everything the way it was and it still wouldn't work.

Replaced my immobilizer fuses, reset the check control/OBC


im out of ideas.
someone please help!!!!

[BMWJNKY]

Hey guys I need some help. I just did this mod and it worked and removed my LBF code but now my car won't start


i need need some help on what I could have possibly messed up... I even tried to reconnect everything the way it was and it still wouldn't work.

Replaced my immobilizer fuses, reset the check control/OBC


im out of ideas.
someone please help!!!!

- - - Updated - - -

Hey guys I need some help. I just did this mod and it worked and removed my LBF code but now my car won't start


i need need some help on what I could have possibly messed up... I even tried to reconnect everything the way it was and it still wouldn't work.

Replaced my immobilizer fuses, reset the check control/OBC


im out of ideas.
someone please help!!!!

Does the engine turn over or does nothing happen when you try to start the car? The car will run with the CCM completely removed from the vehicle so your problem is somewhere else.