GM5 Module repair

[tug]

My GM5 module has gone down & just wondering if anyone can give me some advice. Let me list the symptoms;

1) No central remote locking/opening, doors, boot or filler cap.

2) No window operation up or down.

3) No wipers/screen wash.

4) No interior lighting.

5) Very annoying siren (not car alarm) coming from the battery area. This comes on wether key is in or driving (seems like the zed thinks it has been stolen :lol: )

I have removed the module ready to send off for repair. Has anyone used these people?

https://www.bmwgm5repair.co.uk//url...eading & any advice. Cheers, tug :thumbsup:

 

[ARCS]

I used the guy on ebay for mine. It was only my central locking that was playing up though. Sure it was around £30 and it was back to me within a couple of days.

 

[GasheadIan]

I used the guy on eBay as below
Great service back within 5 days all fixed
Just goggle gm5 repair and links straight to it

 

[bladeowner]

Doesn't sound like OP's issue is just the relay issue which to be honest is just a simple soldering job. Might be cheaper to buy a 2nd hand one and recode to the car. The keys need re programming to the car too with a new GM5

 

[ph001]

I agree. The relays just affect the central locking so there is definitely something else a miss here.

 

[tug]

Thanks for the replies. With what i have read the GM5 controls all of the systems that have stopped working. If the module is removed, then there is no operation in the 5 parameters that have failed in my zed. Here is an excerpt of some of the literature i have read.

"While the GM5 is out of your car several things won't work. Windshield wipers won't work (this could be a big problem if it rains!), interior lights won't work, windows won't go up or down, no alarm functions and of course no automatic door lock control (doors can manually be locked and unlocked as long as the double lock is open.) The car is still perfectly drivable without the module, as long as it doesn't rain. If you think it's going to rain I would suggest waiting or applying some Rain-X. This stuff is amazing and I have driven many miles in the heavy rain without using my wipers at all. It causes the rain to bead up and practically fly off your windshield, it's really amazing. It must be applied when your windshield is totally dry. If it's wet it won't work very well.

I've had cars come in that had bad door lock actuators, some that have bad GM5 modules and a few that have had both! There is no good way to determine if the actuator is bad except to replace it and see. On the GM5 module however the microprocessor checks itself and will log faults with the door lock outputs. The dealer can read these fault codes and determine for certain if the GM5 has a problem with the door lock outputs. If the problem persists after repair/replacement then it is an actuator problem.

If it's only one door then it could be an actuator or the GM5. I checked the schematic and it's possible for the GM5 to give you problems with just the driver door or all the doors expect the drivers or all the doors. If your problem is 1 or 2 out of three passenger doors then it's not the GM5."



I am really confused on this one, everything described here when the module is removed is exactly what i am experiencing with the module connected.

Thanks, tug

 

[Jl-c]

I am sure you have checked but it hasn’t dropped into transit mode aswell just to add to the pain? Some faults could be GM5 as in locking but others transit?

 

[tug]

Thanks for the reply mate, the car drives perfectly but without the operations listed. No loss in power or anything else apart the listed symptoms.

I think i will have to send it off using fastrack post to "cartronics" cos my zed is my only car.

For the repair its gonna cost me over £200! but what can i do

 

[tug]

Here is another excerpt, this describes my problem perfectly;

BMW GM5 repairs - How our service works
BMW GM5 Repairs : Our repair service is fast with 24hr return!

First of all the problem needs to be diagnosed – The GM5 is used to control a variety of different functions. Here is a list of functions this module controls & areas where you might have problems:



Power window control
Remote entry (locking and unlocking via key fob and central locking button)
Boot release (via key fob, handle button and interior boot release button)
Vehicle alarm (siren, tilt & sonar sensors and clown nose light)
Windscreen wiper and washer (both front and rear if equipped)
Interior lights

Just for information to anyone else who encounters trouble with the GM5.

Cheers, tug

 

[Ewazix]

It is a bit odd that all of the GM5 functions have gone down together :?

I think you are saying that the symptoms are the same with the module fitted or removed? so either,
* All of the relays have gone down at once (suspect current overload / short in connections or harness, or power board fault), or
* You have lost current to the module (I'm not sure what fuse it's on?), or
* The ground is bad, or
* The module is not being 'seen' by the main ecu, have you tried removing the battery then reconnecting the GM5? This may give it a chance to 'boot-up'

To eliminate basics I'd read for codes, check you have power to the module, locate the ground and check it's clean and secure, then I think you are stuck with having the module repaired, which my guess is will fix it.

Good luck and keep us updated

 

[tug]

Thanks for the reply mate, yes i have had to disconnect the battery overnight because of the siren (it's not the car alarm) a very loud 1 tone sound that will sound randomly for about a minute then go off, then will start up again randomly.

There are no codes stored in any parameters and the problems still persist after re connecting the battery. My thought was the fuse to the module but i cannot find any information about that. There is a good earth all round the car also.

I am at a loss as to what i can do other than send it off. The zed is parked securely in Leicester at this time as the drivers side window is down & cannot be closed. So i am not with the car.

If anyone knows what fuse to check before i commit good money i would be grateful.

Thanks again Ewazix for the help.

 

[bladeowner]

I have this one you can borrow if it's the same as yours. It's from my 2.5 SMG. It works fine but has a minor problem - it has interference on the the parking sensor line and causes the gong to squawk when activated. Would need coding to your keys which is quite simple if I remember correctly. It would also need coding to the car if you were using it permanently but may give you an idea of whether the GM5 is faulty or the fault lies somewhere else.

 

[Ewazix]

I've not got a link to a fuse or wiring diagram for your N46 2.0, this old help thread has a generic fuse guide https://z4-forum.com/forum/viewtopic.php?f=3&t=38888

There is also this https://fusesdiagram.com/bmw/fuse-box-diagram-bmw-z4-e85-e86.html

Based on these I'd eliminate all fuses associated with the functions that are affected, in particular No 8, 10, 11 and 12. (In fact I'd probably check them all and have a poke in the fuse box in the engine bay, it's amazing what knock-on effects a fuse can have on apparently unrelated functions)

BTW what is the beeper in the boot, PDC? if so that apparently shares fuse 8 by the looks of it, elimination is key but my guess is all fuses will be OK and relays have 'fallen over' in parallel with a component on the module. That's based on logic rather than any specific knowledge, I just like a puzzle

edit........... I've just read Blade's post as we crossed, the mention of interference on the PDC interesting.

 

[tug]

Well, thankyou all so much for the replies/help & thanks a million to bladeowner for the offer

GOT IT SORTED! it was fuse 10! the little bugger had given up the ghost :lol:

So you great folk where all on the right path & i thank you all for the help/ advice. I got the idea to check out fuse 10 from this post by Finisterre;

https://z4-forum.com/forum/viewtopi...ys & this place. Cheers all, tug :thumbsup:

 

[bladeowner]

 

[Ewazix]

Fuse 10 :yu:

It pays not to panic and eliminate the basics, glad it's a cheap fix




........... But why did fuse 10 blow?

 

[tug]

Thanks for that mate. Now you've got me worried again

Not really if it blows again i will then start to fret a bit :?

Cheers Ewazix, tug

 

[ph001]

Bit of a long shot - but try opening and closing the centre drop down console between the front seats a few times. The wiring that runs through here has a habit of breaking and shorting out. That certainly kills the fuse that runs the ICE, not sure if it could affect Fuse 10 though.

 

[ph001]

New relays now in stock if anybody needs them changing on my their GM5 module. £40 + p&p.