E39 549 LCM Issue?

[Greg130]

Hi Guys,

Just after a bit of advice.
Ok so I have recently bought another 1998 E39 540 and having a couple of issues.

No dash/instrument indicator, high beam, fog lamps warning lights ect. The lights (indicators ect) all work perfectly fine just not getting the tell tail lights on the dash.
Also no check control function.


Plugged in bmw scanner 1.4, NCS expert and DIS, all report no LCM module present, so completely dead and not talking to the car or software.
Have checked to make sure that the LCM is there, all present and plugged in.
Checked the two fuses in glove box, all good.

So I'm thinking dead LCM?
Or could it be a power supply issue, apart from the 50amp under the floor (not yet checked) am I missing any other fuses or relays?

Any ideas or has anyone had this issue before?

Cheers

[JimLev]

Do all of the outside lights work?

[Greg130]

Yes all the outside work.
Do have a lot of dead pixles in the instrument cluster, not sure if its related.

[Keith Nguyen]

Check all fuses, disconnect the battery cable for a bit and plug it back in. The LCM seems to be functioning as its activating the lights. I had a similar issue when my LCM didn't respond in the same manner and my whole navi went out. I started by disconnecting the navigation and audio components from the car, then disconnected all the all fuses pertaining to audio and telematic system in the trunk and glove box. When I put the fuses back, my cluster started to work normally again. I suspect disconnecting the battery for a while would perform the same task.

By the way, this all happened with a weak battery installed. I charged it and seems to be working like a champ now. Good luck!


--=Keith

[Greg130]

Check all fuses, disconnect the battery cable for a bit and plug it back in. The LCM seems to be functioning as its activating the lights. I had a similar issue when my LCM didn't respond in the same manner and my whole navi went out. I started by disconnecting the navigation and audio components from the car, then disconnected all the all fuses pertaining to audio and telematic system in the trunk and glove box. When I put the fusses back, my cluster started to work normally again. I suspect disconnecting the battery for a while would perform the same task.

By the way, this all happened with a weak battery installed. I charged it and seems to be working like a champ now. Good luck!


--=Keith

Thanks, will disconnect tonight and re check all the glove box fuses.
Any other fuses for the LCM, I read somewhere that certain vehicles also have a relay?

[Greg130]

The 50amp fuse under the carpet, its a RHD car so this would be located under the drivers seat?
Also thinking if this had blown then none of the lights would work? (50amps seems very high just for the LCM?)
I did have a peak under there yesterday, couldn't see the fuse box as only managed to pull the carpet back a little, no signs of water damage and bone dry.

Also thinking if I do a voltage test on the LCM fuse slots in the glove box this will confirm if there is power to the LCM?

[StRaNgEdAyS]

Yes, it would be under the drivers seat.
You'll have to unbolt the seat, lift the carpet, then lift the foam pieces covering the fuse box.


Sent from my G8141 using Tapatalk

[Greg130]

So quick update on the situation:

Disconnected the battery for an hour.
Checked all fuses again, apart from the 50amp under seat.
Checked plug in wiring connections on LCM, ZKE.
Disconnected IKE and reconnected.

Reconnected the the battery and crossed fingers.........Instrument cluster dead, on board computer display dead (above a/c)..............blast!!
Disconnected IKE and reconnected 3 times then bingo in springs into life........phew!!!
Still no check control or instrument indicator lights ect.

Ran BMW Scanner, no LCM, exactly as before.

So now I'm thinking is it a fault with the IKE or LCM?
Everything else works, all electrics, lights, windows, sunroof, pdc, ect.

Also checked the voltage to the two LCM fuses in the glove box, all good.
Also checked battery voltage 12+ volts, charging at 14+ volts when engine running

Any thing else I can check or try before I start buying parts?

Do the two glove box fuses take power from the 50amp fuse under the seat? (kind of thinking that is probably ok)

[Keith Nguyen]

So weird... Does the radio work? Do you hear audio feedback from the turn signals?


--=Keith

[Greg130]

So weird... Does the radio work? Do you hear audio feedback from the turn signals?


--=Keith

Yes radio works, cd works, everything works apart from the check control functions/messages and instrument indicator/high beam lights ect......................no audio feedback from turn signals.

Thing is its a fairly low millage vehicle (140,000 kms), 2 previous owners from new, heaps of service history and a pile of invoices detailing every cent spent on the car over the years.
From what I can tell its all original, nothing looks to have been hacked about with or messed with.

But yes very weird, faulty LCM or Instrument cluster?

[Keith Nguyen]

See if the cluster responds to the diagnostic tests in INPA. If so, I'm leaning on the LCM being faulty.


--=Keith

[Greg130]

See if the cluster responds to the diagnostic tests in INPA. If so, I'm leaning on the LCM being faulty.


--=Keith

Good idea, will plug it in tomorrow, cheers😃

[geargrinder]

These kind of electrical things always blow. The "disconnected IKE 3 times, then..." makes me look right at the cluster. Maybe bad connector on the wire or bad connector on the PCB in the cluster etc.

Here's a factor to consider... The IKE acts as a critical comms gateway for the car. More than most people realize.

You can't get to anything except the 'core engine & chassis modules' without going through the cluster. So very well could be the cluster is not comm'ing w/ the K/I bus systems properly.

That wold be consistent with having BC problems and LCM problems and the IKE not getting the signal from the LCM to 'turn on the cluster illumination'.

So the question is, is the I-bus down entirely, or is it just isolated modules? A quick and dirty check for the I-bus devices is whether the steering wheel radio buttons or the hazard flasher button works. If they don't, then likely the entire I-bus is not communicating and is being 'taken down' by a faulty module or short. If those DO work on their own, then most likely its the IKE that is having trouble w/ the i-bus.

[Greg130]

Agreed, i was sure it was the LCM but having to re-connect the IKE 3 times to get to fire up adds that element of doubt.
See how it responds to inpa tomorrow.
Will also check the radio buttons on steering wheel, i know the cruise control buttons work but not tried the radio ones.

Appreciate the input guys.

[geargrinder]

having to re-connect the IKE 3 times to get to fire up adds that element of doubt.

Yeah not just that but the other non-LCM related issues.

Although if cruise works then the MFSW should be able to talk to the IKE therefore maybe I bus is OK...

Let us know what you find!

[Keith Nguyen]

Interesting... Good points


--=Keith

[edjack]

The LKM only controls external lights.

[Greg130]

Yeah not just that but the other non-LCM related issues.

Although if cruise works then the MFSW should be able to talk to the IKE therefore maybe I bus is OK...

Let us know what you find!

Can confirm all MFSW functions work correctly and radio station information appears on the dash display and MID display.

Will test IKE with INPA when I get home from work this evening.

[geargrinder]

But the IKE and LCM communicate so that the night time instrument lights come on when the exteriors are turned on.

- - - Updated - - -

(that was answering Ed).

Greg you might try having car turned on and cluster loose so you can wiggle the connectoronthe Ike and see if things flicker and act up. Probably don't try that while driving but engine off sitting still should be ok.

[Greg130]

But the IKE and LCM communicate so that the night time instrument lights come on when the exteriors are turned on.

- - - Updated - - -

(that was answering Ed).

Greg you might try having car turned on and cluster loose so you can wiggle the connectoronthe Ike and see if things flicker and act up. Probably don't try that while driving but engine off sitting still should be ok.

Yes the instrument lights come on when the external lights are on.

Will try wiggle the IKE connections tonight after doing INPA test.

Also tried Test 02 on the OBD hidden menu this morning, all good, all instrument lights and gauges worked.

One thing I did forget to mention is that the "low brake fluid" light is constantly illuminated on the dash. (have checked brake fluid level, all good)
On my previous E39 this was also the case, only managed to fix it by replacing the LCM and coding it to the car, kind of assume its all related to what ever is going on.

Have ordered a replacement LCM, I'm in Australia so it will take a couple of weeks to get here from ebayland.

One constant is that BMW Scanner, DIS ect all report no communication with the LCM.
BMW Scanner also reports an error in the DME saying "no LCM power up"

Don't you just love E39's :-) Actually I do lol but will love it even more when this glitch is sorted.

[geargrinder]

Huh. Low brake fluid light has nothing to do with the LCM. If you recoded the car it could have recoded all kinds of things and reset a bug in the cluster I'm suppose.

[Greg130]

Huh. Low brake fluid light has nothing to do with the LCM. If you recoded the car it could have recoded all kinds of things and reset a bug in the cluster I'm suppose.

That was on my previous E39, no idea if its related to this ones current issues, just seems like a bit of a coincidence?
The previous one had an LCM 1 fitted by PO, I swapped it for an LCM 3 which solved the brake fluid level issue. Anyway guess that's kind of off topic with this cars electrical glitch.

[Greg130]

Tried INPA on the car, I could activate all instrument cluster lights via INPA.

Same deal as all the other software, INPA was unable to communicate with the LCM.

[Keith Nguyen]

I still think it's your LCM... We'll soon find out!


--=Keith

[Greg130]

I still think it's your LCM... We'll soon find out!


--=Keith

Yes I'm thinking so, ordered one but will take a couple of weeks to get here, will report back on what happens.