Whats the deal with LCM's and LED rear lights??

Originally Posted by Bandersnatch

I don't think this is exactly true. Certainly the dealer won't flash a used replacement LSZ because it stores information about the car's mileage. That's why you get a tamper dot if you swap in a different LSZ. And I'm not sure whether this is a simple thing for an Indy to do. Or whether they'd be nervous about doing it.

Pretty sure it is. IDK maybe because I have done it and know others who have.

For what it's worth, the service department at Tischer in MD (they sell an OEM retrofit kit) said they could program my LCM (not all dealers can do it), and that the reprogram would cost $140 (!?!). When I suggested this was steep (the BMW service guideline estimates 1 hr shop time to install the lights AND reprogram -- I only needed to reprogram. Anyway.... I went to a local independent (in Manassas, VA), and they were able to reprogram it for me. Works perfectly. $50 out-the-door.

Originally Posted by Bandersnatch

I don't think this is exactly true. Certainly the dealer won't flash a used replacement LSZ because it stores information about the car's mileage. That's why you get a tamper dot if you swap in a different LSZ. And I'm not sure whether this is a simple thing for an Indy to do. Or whether they'd be nervous about doing it.

But it sounds like Jaymemaurice has almost solved this problem in a different thread where he upgraded an '01 330ci to have rain-sensing wipers and auto headlights.

http://forum.e46fanatics.com/showthr...=746918&page=2

He used NCS expert (?) and was able to change the VO on his new LSZ to match his car. He's still working to get the AIC working (whatever the hell that is) and then will upgrade his DIY.

Ian, if you don't mind, I'd love to hear you translate all this into English. I'm going to have to do this at some point. So I guess the question is what is the easiest/cheapest/best way to accomplish what the OP is asking, but on a pre-2002 car?

Thanks in advance.

In english (as best I can do)

If you have an E46 produced before 09/2001 (check your driver's door jamb), you will need to replace your LSZ if you wish to install factory LED tail lights.

If you feel for some reason that your LSZ might have been replaced at some point (highly unlikely), then you will need to remove the left side trim surrounding the switch and remove the switching unit. On the label, you will see the part number, manufacturer and at the bottom, a HW and SW level. You must have a SW level higher than 2.0 for the unit to accept the LED Retrofit. If your switch says SW:2.0, then the retrofit will not work.

The LSZ stores mileage at 100 KM intervals sent from the cluster via the I-bus. For this reason, BMW has created a set of rules about the LSZ. One of those rules is that if it need be replaced, only a NEW, UNCODED unit may be used.

If you have determined that you will need a newer LSZ and you want factory LED tail lights you have one official option and 3 un-official options:

The Official Option: You will need to purchase a NEW, UNCODED LSZ. Then, it must be coded to your car. Finally, perform the LED taillights retrofit coding and you're done. Check faulkner BMW for a good price. Should be somewhere in the low $300's.

"Other" options:

1: you can purchase a used LSZ from a newer model. This will illuminate the tamper dot on your cluster and depending on the vehicle it was removed from, your lights may not function correctly.

2. You can find someone capable of "virginizing" the LSZ or changing the mileage and VIN.

3. You can install resistors to match that of the incandescent bulbs. However, you will still have flickering of the bulbs at startup.

Originally Posted by SWINFORD

True to an extent all you gotta do is get is reflashed


OP I have done the OEM retrofit mine did the same thing when they didnt set them right. Make sure they know how to do the retrofit if not go somewhere else.

Not true. BMWs official tools are incapable of changing the VIN that's already stored on an LSZ. No dealer can do it, no matter how much you ask or offer to pay them. And unless the VIN on the LSZ matches your car's VIN, you'll get a tamper dot - Even if the mileage is *exactly* the same as what's on the cluster.

Originally Posted by TerraPhantm

Not true. BMWs official tools are incapable of changing the VIN that's already stored on an LSZ. No dealer can do it, no matter how much you ask or offer to pay them. And unless the VIN on the LSZ matches your car's VIN, you'll get a tamper dot - Even if the mileage is *exactly* the same as what's on the cluster.

Then how did mine work? And when I did my sisters and a buddies?

Bump for great info

All you need to do is grab PA Soft.

Disable all lamp warnings in the software on the rear lights, write to LCM.


Job done! no more flicker, works on all models.

I have pasoft 1.4.0, but no warm check options. How can that be?

what does the lcm control

I understood it is the light control module. Like headlight, indicator, break lights etc.
Also more complicated function as automatic vertical headlight aiming or even adaptive headlights (steering dependent lighting).

check out my thread i started and see what you think