Electrical LCM issue, my own stupid fault 🤬

[thecremeegg]

OK, I've managed to source a replacement LCM & have fitted it after a chat with my local indy round the corner. And yay it works , all lights back to normal.
I have the tamper light on as expected but also the airbag light :? . Maybe there's a tie in with the 'new' LCM as it wasn't on with the old one & I had the battery disconnected the whole time. Anyway no biggy hopefully, she's going in tomorrow morning to have everything reset & coded .

The LCM needs to be a lower mileage than the car is on as they have to match the two together - the LCM holds the mileage for the car, hence the tamper light. You can add miles but not take them away. Hopefully it's just something that can be reset.

I hope that's not the case. How would anyone selling a used LCM know what mileage the recipient car has on it? I certainly have no idea what mileage my replacement LCM has on it but I presumed the LCM was a backup for the speedo mileage.
My indy round the corner couldn't do the job as he couldn't access the LCM with his software. It's now booked in for 22nd June to be coded by the BMW indy I mentioned earlier. At least I can drive it now :driving: .

I think it is I'm afraid! It's to stop you adjusting mileage down

 

[ronk]

This might be a silly question but ??? If miles can be added, what happens when it goes over the 999,999 max - does it then go to 000,000 ?

 

[ph001]

There is no issue in coding any mileage lcm to the car. The light will definitely not go off by itself when the two mileages ‘catch up’. Where on earth do you dream this stuff up from?

 

[oldgitdave]

There is no issue in coding any mileage lcm to the car. The light will definitely not go off by itself when the two mileages ‘catch up’. Where on earth do you dream this stuff up from?

That's good to hear .

 

[ronk]

.

 

[ronk]

The LCM needs to be a lower mileage than the car is on as they have to match the two together - the LCM holds the mileage for the car, hence the tamper light. You can add miles but not take them away. Hopefully it's just something that can be reset.

No dreaming ph001
It seemed like a logical question to ask after reading this.

 

[enuff_zed]

The LCM needs to be a lower mileage than the car is on as they have to match the two together - the LCM holds the mileage for the car, hence the tamper light. You can add miles but not take them away. Hopefully it's just something that can be reset.

No dreaming ph001
It seemed like a logical question to ask after reading this.

No such thing as a stupid question. If you don't ask you don't learn.

 

[ronk]

The LCM needs to be a lower mileage than the car is on as they have to match the two together - the LCM holds the mileage for the car, hence the tamper light. You can add miles but not take them away. Hopefully it's just something that can be reset.

No dreaming ph001
It seemed like a logical question to ask after reading this.

No such thing as a stupid question. If you don't ask you don't learn.

That’s what I was always told as well

 

[oldgitdave]

No dreaming ph001
It seemed like a logical question to ask after reading this.

No such thing as a stupid question. If you don't ask you don't learn.

That’s what I was always told as well

I've asked a few daft ones in my time I can tell you :roll:

 

[kis]

Might just be the vin number. My airbag ECU needed the vin coded. I don't think it had the mileage coded. Could be wrong... Get them both done, if it's still going in anyway

 

[thecremeegg]

There is no issue in coding any mileage lcm to the car. The light will definitely not go off by itself when the two mileages ‘catch up’. Where on earth do you dream this stuff up from?

http://www.bimmerboard.com/members/q/original/Odometer%20Tamper%20Dot.jpg

please note number 4.

Always been told this, if it's wrong it's wrong but yea, take the risk if you want!

 

[oldgitdave]

Might just be the vin number. My airbag ECU needed the vin coded. I don't think it had the mileage coded. Could be wrong... Get them both done, if it's still going in anyway

There is no issue in coding any mileage lcm to the car. The light will definitely not go off by itself when the two mileages ‘catch up’. Where on earth do you dream this stuff up from?

http://www.bimmerboard.com/members/q/original/Odometer%20Tamper%20Dot.jpg

please note number 4.

Always been told this, if it's wrong it's wrong but yea, take the risk if you want!

I was told the VIN would need to be coded at the same time. My BMW indy never mentioned that the replacement LCM should have less miles on than my car. How would I know in any case :? . I will find out next Monday.

 

[thecremeegg]

Yea the VIN is fine, it's just the mileage that I've always been told CANNOT be amended down, for obvious reasons. Guess we'll find out like you say! I hope that it isn't the case and I'm wrong, but yea, it's been discussed on here before and it's always been said you need one with a lower mileage :idunno:

 

[oldgitdave]

Yea the VIN is fine, it's just the mileage that I've always been told CANNOT be amended down, for obvious reasons. Guess we'll find out like you say! I hope that it isn't the case and I'm wrong, but yea, it's been discussed on here before and it's always been said you need one with a lower mileage :idunno:

Perhaps I'll get lucky then :wink: . I doubt it though knowing me :x .

 

[Argyll Andy]

Yea the VIN is fine, it's just the mileage that I've always been told CANNOT be amended down, for obvious reasons. Guess we'll find out like you say! I hope that it isn't the case and I'm wrong, but yea, it's been discussed on here before and it's always been said you need one with a lower mileage :idunno:

Perhaps I'll get lucky then :wink: . I doubt it though knowing me :x .

Don’t know if it’d work or cost but what about one of these “mileage corrections” services.

Quite a few years ago I changed the clocks on car and wanted the correct mileage showing as it was really low mileage fsh and there was a Z4 and E9x in at the same time. I remember the guy saying they were a complete PITA to do as the mileage was recorded in several ways/places (can’t remember which one) but remember him saying he needed all keys etc for the car and it took twice as long and twice the price

 

[ronk]

I would say that given the age of the car and it’s potential value - I would be tempted to leave it alone if it will cost a lot to rectify.
Keep documentation of the change and maybe print these pages for a any prospective new owner.

The only thing that would bug me is that that tamper light

 

[ph001]

I’m 95% sure you can just code the mileage in the LCM module to match the dash readout. It’s the other way around that you can’t do..... although I must admit that .pdf seems to suggest different! There was a post way back in 2015 I think where someone had succeeded.

 

[thecremeegg]

I’m 95% sure you can just code the mileage in the LCM module to match the dash readout. It’s the other way around that you can’t do..... although I must admit that .pdf seems to suggest different! There was a post way back in 2015 I think where someone had succeeded.

Hope that's the case for sure! Of the two of us, I want to be wrong hah!

 

[ronk]

It’s witchcraft!

 

[oldgitdave]

Evening chaps .
Well my BMW indy has managed to re-code the LCM & we're good to go :yeah: . However I did have some doubts earlier on today. He called me around lunchtime to say he was struggling & would need the car for longer. He went so far as to say I might have to have it back unfixed . He ended up removing the LCM & had to connect directly to it to do the job.
When I dropped it off he said he'd have to copy the details from the dash & load that info on to the LCM after deleting the details the LCM held, pretty much as ph001 said .
So tomorrow morning I can collect her & she won't have the dreaded tamper light or airbag light on . TFFT! I think I've aged 10 years worrying about it this last week ldman: . All I've got to do now is pay for it!