Fix for infamous LBF problem

[RRSperry]

Sorry but I still doesn't make sense. In the 9 years I've had HID's I've never had the gauges jump.

I still say, they really aren't related, in causal way. There is an underlying problem. Current spikes are unusual, that's what the battery is for. If it was just that, then the gauges should jump when your amp pull a lot of current too. And... what spike there is, maybe what 9 amps, is so short in duration, (current dies off as V increases at the ballast) there is little to no danger to the wiring. Just because you two have the same problem doesn't mean it's a PROBLEM.


Jim Powell (Apexcone) is selling HID that do not give a lbf.

If I were too guess, I would say you have a bad ground, or sktechy ballast, or some other problem.

[psu325i]

Sorry but I still doesn't make sense. In the 9 years I've had HID's I've never had the gauges jump.

I still say, they really aren't related, in causal way. There is an underlying problem. Current spikes are unusual, that's what the battery is for. If it was just that, then the gauges should jump when your amp pull a lot of current too. And... what spike there is, maybe what 9 amps, is so short in duration, (current dies off as V increases at the ballast) there is little to no danger to the wiring. Just because you two have the same problem doesn't mean it's a PROBLEM.


Jim Powell (Apexcone) is selling HID that do not give a lbf.

If I were too guess, I would say you have a bad ground, or sktechy ballast, or some other problem.

RRSperry - Sketchy ballast could be what we are experiencing?? I didn't have a problem with my gauges until I installed my HID kit. More importantly.. the gauges ONLY dip for the 1 second that I flip my headlights on. Once the HIDs are on, the LBF error stays obviously, but the guages return to their normal position. The concern is that this surge of power (or lack of power) could have consequences over time. I don't want to see my DME/wiring/etc get damaged just so I can have some super bright headlights. You dig it?

[LuxoM3]

Gentlemen:

FWIW - I HAVE the Jim Powell / Apex Cone/ DDM HID lights. I get the LBF error and I GET the jumpy gauges when I turn on my HIDs. Heck I even bought the Apexcone LBF module which fools the Check Control into thinking the voltage is correct. (It didn't work BTW)

But I'm not mad because I did my homework on the HIDs.

Some BMWs allow you to just plug in the HID kit and all is well...
But some others... well... and mine is one of the others.

And doing a search some people have gone months or years without the LBF error and BHAM! one day it appears.

Anyway... if you guys look HARD, on the understeer and apexcone site... there is for sale a "wiring harness relay for HID" which is pretty much a direct power link to the battery, a 9006 pickup for turning on the lights (signal) and another 9006 connector to the ballast (power). This by passes the stock wiring for it's power source.

This is how PIAA power's it's HID lights... it won't solve the LBF error (no biggie), but should completely resolve the gauge jumps as the light control box won't freak out anymore.

There's another post I have where I ask Jim about getting me a wiring diagram and I mention the gauge jump. He suggested a 10amp fuse... which I put in and it works most of the time. He did mention a power surge of sorts... related to the ballast pulling voltage to charge itself up to spark the igniters.

[LuxoM3]

Reloc:

"I must be extra thick this morning, but I still don't understand what Luxo did- what H1 headlights are those extra connetors being plugged into?"

The extra connectors are the ones that originally plugged into the H1 bulb in the head light.

[Gofast]

To follow up, here are some pictures of my wiring.
The wire I used is 12 AWG, with PVC casing. I found some wire at an electronics shop that specifies "gas and oil resistant" on the casing. I figured that would work well for being in the engine bay.

You can see where the wires come out from the fusebox. Sorry, but I really don't want to pull open the fuse box just for a picture; once you do it's hard to get all the wires back in there.


I pretty much ran parallel to the stock harness, you can see where the driver's side goes down to the ballast (my ballasts are down on the bumper core), and the passenger side goes over the top of the radiator to the other side.


Hopefully that helps anyone who is thinking about doing this.

[LuxoM3]

Go - so what you are doing is tapping into a higher power source from the fusebox to give a more stable power supply to the HID ballasts?

I ask as I got an HID relay (9006 connectors and a cable to reach the battery). With your photos, it looks like I can just pick up a 12 volts source from the bottom of the fusebox?

[Gofast]

Go - so what you are doing is tapping into a higher power source from the fusebox to give a more stable power supply to the HID ballasts?

I ask as I got an HID relay (9006 connectors and a cable to reach the battery). With your photos, it looks like I can just pick up a 12 volts source from the bottom of the fusebox?

Yes, there are plenty of 12V sources inside the fusebox.

On the headlight side of the relay, the circuit used to go:
Relay-> Fuse-> OBC-> long OE wire to headlight-> Headlight-> Ground

This is repeated for both the right and left headlights.

I cut the wires just after the fuse, and spliced in my wires direct to the ballast. Notice that this also cuts the OBC out of the circuit. My circuit now goes
Relay-> Fuse-> New 12 AWG wire -> HID ballast-> Ground

However, I found out through experience that doing this, on my car at least, caused the OBC to throw a LBF message all the time, with or without the lights on. I guessed that the OBC was looking for ground on the low side of the circuit, and, not seeing it, assumed the headlight bulb was out. Since the OE headlight wires are still attached to the low side of the OBC's circuit, I connected them directly to the ground down on the headlight end. That fixed it, no more LBF ever.
So the OBC circuit now goes
OBC->long OE wire to headlight->Ground
This circuit is now completely independent of the headlights (although the OBC doesn't know it).

[a554255]

my headlights don't come on period any help......

[GR7]

Just did this, works perfectly. I just twisted the wires and used heat shrink wrap.

[BL4CK-OUT]

Finally got around to doing this. No more LBF!!!

However, I gave up trying to pull out the CCM. After a good half hour of writhing in pain trying to yank at it, I just decided to trace the wires and snipped them.

[///w3fl3x]

Where did you guys buy your molex connector from?
I went to shuck's and radio shack and both did not have it.

Or did most just connect the wires together and called it a day without the molex connector?

[M13]

Will the new 55w HID kits available today solve the LBF issue?

[///w3fl3x]

Will the new 55w HID kits available today solve the LBF issue?

No i still get it with my 18 button obc.

Never had that code until i installed the 35w kit then upgraded to the 55w kit 6 months ago and still get the code. I got the code eliminator and that didn't work either.

[Bav///Man]

Where did you guys buy your molex connector from?
I went to shuck's and radio shack and both did not have it.

Or did most just connect the wires together and called it a day without the molex connector?

IIRC, the molex connector just makes the wiring a little cleaner and also makes it easier to undo the LBF fix should you choose to do so in the future.

Otherwise, what you're saying should be fine.

[themadrussian]

It is the HIDs. That's why the gauges jump when you turn the headlights on.
The steady-state running of the HIDs isn't really a problem, but the high amperage required for a split second to power the HID igniter is a problem.



It isn't really a matter of "robustness", but rather a matter of wire gauge. A certain gauge wire is required to carry a given current, and this is magnified as the wire gets longer. The stock harness isn't heavy enough to comfortably carry the current required to ignite the HIDs, and the long wire from the fusebox to the headlights exacerbates the problem. So when you turn the HIDs on, you get a current spike as the system attempts to push too much current through the long, thin stock harness. Even if you aren't blowing fuses, the gauge jump is a symptom of pushing the system too hard. Some people don't even have the gauge jump initially, but develop it over time as the OE harness begins to wear. If you keep running the stock wiring, odds are that you will get the gauge jump, and then start blowing fuses, and eventually burn up your harness. Remember that a blown fuse is the system trying to save itself from damage.
In my case, I solved this by running a heavier gauge wire from the headlight fuse in the fusebox to the HID ballast. There is still a short length of the original gauge wire between the headlight relay and the fuse, and another in the OE headlight connector that plugs into the igniter/ballast, but both are very short, so it doesn't matter much.
Now that there is heavy wire in the long circuit, viola! no more gauge jump. Also, keep in mind that the current spike is across the entire system, so while the gauge cluster is the only immediately visible symptom, the ECU and other electronics are also seeing the spike and possibly sustaining damage.

Yes, which is why you need a wiring harness that powers directly off the battery. I don't know if a 12V in the fusebox will be safer.

I have a harness that goes like this:

Positive battery terminal > 30A Fuse > Relay (input from one low beam plug, output to two new 9006 plugs) > HID Ballasts (driver and passenger)

You only need one stock low beam plug to activate the relay - the power comes straight from the battery and is consistent, and most importantly, can handle the 10-20A current spike (my LVQ212 ballasts say the max current is 20A).

As a result, of course, I get an LBF (seeing as one of the low beam plugs is totally unplugged, and the other is merely triggering the relay).

The guage dropping is definitely due to the conditions mentioned above. A spike in current for the igniter...

Yes. Get/make a relayed wiring harness like the one I have.

Go - so what you are doing is tapping into a higher power source from the fusebox to give a more stable power supply to the HID ballasts?

I ask as I got an HID relay (9006 connectors and a cable to reach the battery). With your photos, it looks like I can just pick up a 12 volts source from the bottom of the fusebox?

Pick it up from the battery terminal itself. Safer that way. Circumvents the weak stock wiring entirely, although in theory the 12V at the bottom of the fusebox should be going straight to the battery anyway... still, better safe than sorry. The battery terminal is easily accessible in the engine bay - just hook it up there, run it to your passenger side low beam plug, and then run it above the radiator where the stock wiring harness goes (there are clips, even!) to the driver's side.

[LuxoM3]

Agreed . I am running a relay harness - don't believe the "you don't need a harness" naysayers... for *some* BMWs, the lighting control module is pretty sensitive or the wiring isn't up to snuff to carry a voltage spike to power up the ballast/igniters.

The harness runs right off the battery power (source is the battery terminal on the exhaust/passenger side)... from there a relay box picks up signal from your passenger headlight connector... and from there 2 wires run out of the relay box to power the headlights.

It's a pretty clean set-up and barely a 30 min install - and most of that time is taken undoing the battery terminal cover and maybe removing the front bumper so you can route your wiring cleaner.

[themadrussian]

Agreed . I am running a relay harness - don't believe the "you don't need a harness" naysayers... for *some* BMWs, the lighting control module is pretty sensitive or the wiring isn't up to snuff to carry a voltage spike to power up the ballast/igniters.

The harness runs right off the battery power (source is the battery terminal on the exhaust/passenger side)... from there a relay box picks up signal from your passenger headlight connector... and from there 2 wires run out of the relay box to power the headlights.

It's a pretty clean set-up and barely a 30 min install - and most of that time is taken undoing the battery terminal cover and maybe removing the front bumper so you can route your wiring cleaner.

I'm still flummoxed about disabling the LBF. I can go with Braymond141's method (http://forums.bimmerforums.com/forum...php?p=13494216), which requires no wiring or splicing, but disables the entire OBC Check Control system, or I can go with the method described here. Hrm.

[ozarkbikeracer1]

To the original poster of this thread "thank you very much!" It worked great once I hooked up the right wires. I tried to be too smart by half and not remove the CCM before I cut the wires, but I got one wrong, so I had to remove it anyway. It sure is nice to turn on my headlights and not get that damned LBF.

[soulrebel]

BUMP, just did this! thanks!

[bmxmett318]

I'm still flummoxed about disabling the LBF. I can go with Braymond141's method (http://forums.bimmerforums.com/forum...php?p=13494216), which requires no wiring or splicing, but disables the entire OBC Check Control system, or I can go with the method described here. Hrm.

I'd vote on disabling the OBC before cutting wires if you are diligent about maintaining your fluids and checking lights etc.....Judging by the looks of your Estoril I'd say you do a half decent job

[Brent 930]

I finally got around to investigating the LBF issue I was having with my car like many others. I suspected there was a shunt to monitor the amount of current the bulb was drawing, and I was right. My car had HID's when I bought it and I was getting the LBF. When I switched to stock, yet using high beam bulbs for the Low, it still triggered the fault. I initially thought it was because of the high beam bulb used in the low beam spot. From additional reading on the forum that is incorrect.

It seems if you install HID's without the fake out circuit being installed at the same time you will damage the shunts in the control box (makes sense to me). So unless you get a new control box (if you're going back to stock) or do this mod as described you will get the LBF endlessly. Instead of cutting the wires I looked at my Bentley and inside the control box first, and then this thread. I ended up modifying the control box instead. So far so good as I don't get the LBF anymore.

If anyone is interested in doing this let me know.

[projecth]

Will this fix work for a 1998 528i??

[Brent 930]

Will this fix work for a 1998 528i??

If it has the same circuitry then yes.

[projecth]

I guess the only way to figure that out would be to open it up and check the wires??

[Brent 930]

Via the Bentley and compare would be the way.