06 BMW z4m Coupe, GM5 module (potential) replacement

MatteH Oxford · 18 Aug 2013 at 21:45

I've got to take a look at one of these for a one touch window fault, do they require programming to the car if replaced?. I'm not sure if they are linked via a canbus system to any other modules.

I have the wiring diagrams & the pin in/outs for testing purposes.

[TW]Fox · 18 Aug 2013 at 22:11

Is the fault that it wont one-touch-up anymore?

MatteH Oxford · 18 Aug 2013 at 22:19

Both ways AFAIK on the driver side, the passenger side is apparently working O.K.

The owner (a friend's fella) has tried a reset via holding the switch a certain way, to no avail, but I'll check that with two reset methods floating around the net I've found.

I'm presuming the one touch operates by pushing the switch past a point of resistance?

[TW]Fox · 18 Aug 2013 at 23:04

Correct, and if the battery has been off it does tend to reset it and stop it working until its set back up again. I doubt there is anything physically broken.

MatteH Oxford · 18 Aug 2013 at 23:25

It's unusual that it doesn't work both ways, usually if one way is faulty then that suggests a switch, bad connection or a trap sensor fault. Both directions suggests a relay/transistor issue to me which would normally be within the module - again, that's afaik (at least I think I know) about these cars. It might just be simple like the connector on the module or switch, I can't say without looking tbh.

At least access is good for the module, looks quite easy to get to. The actual switch is of course a doddle to pop out.

mjt · 19 Aug 2013 at 09:35

My driver's side window doesn't one-touch close. What could this be? A bad connection?
It works about once every six months, probably when the planets align.

MatteH Oxford · 19 Aug 2013 at 17:43

Quite often it's the trap sensor that's been tripped or damaged ikf the one touch close isn't working, it's a strip that runs along the top edge of the door where the glass slots into the rubber seal. Or it may well be a dodgy connection or switch.

morfmedia · 19 Aug 2013 at 19:38

One touch up doesn't work with the door open I think (or possibly one touch down?) so could be a door open/closed sensor?

mjt · 19 Aug 2013 at 20:03

MatteH Oxford said:
Quite often it's the trap sensor that's been tripped or damaged ikf the one touch close isn't working, it's a strip that runs along the top edge of the door where the glass slots into the rubber seal. Or it may well be a dodgy connection or switch.

The windows are dodgy anyway, they have a habit of going down at an angle, so I'm sure it's related.
The trap sensor kicks in while closing quite often.

It's a common fault on the Z3 but I think it's quite a big job faffing with the window regulators.
I have no idea what I'm doing and there are side airbags, but maybe it's not has hard as I imagine.

MatteH Oxford · 19 Aug 2013 at 20:25

morfmedia said:
One touch up doesn't work with the door open I think (or possibly one touch down?) so could be a door open/closed sensor?

I would have thought that would affect the interior light and door ajar notification.
The Z4M issue occurs with both doors closed, and neither the up or down ''one touch'' function works on the driver's side.

A friend comes back from Portugal next week, he used to work at North Oxford BMW and has diagnostic software with programming capabilities.

If the module isn't programmed for this function, so a software fault can be ruled out, then it's a case of checking to see if the module is receiving commands from the switch and returning them to the window motor.
The fault would be somewhere in the circuit from switch to module to motor. All that you do is check for the correct voltage at each point and see where the break is - hopefully not at the module pins that feed the wire that goes back to the motor.

MatteH Oxford · 22 Aug 2013 at 05:08

MatteH Oxford said:
hopefully not at the module pins that feed the wire that goes back to the motor.

Ignore ^^ - there would still be power at those pins as the windows as there is only one set of wires powering each motor, they do still work up/down if the switch is held.

I had a look & I'm certain the module is at fault. I have continuity (good 12.2v) from the switch to the module when the one touch function is requested, the module power/earth is good and of course the window still goes up/down during manual switch operation.

There's no voltage at the anti-trap input pins on the module either, passenger side one touch works o.k.

MatteH Oxford · 23 Aug 2013 at 12:29

Chappy got himself a 2nd hand module & installed it himself, the windows now work properly but the remote key opening needs programming by the sounds of it.

rG-tom · 23 Aug 2013 at 14:31

How strange, my passenger side window has one touch down but not up, yet the car can control the up ok when closing the roof etc?

Do I need a new module? It's the same regardless of which switch I use

MatteH Oxford · 23 Aug 2013 at 16:18

Probably, find the correct pin at the module using continuity tests, if the voltage is there when you press the switch for one touch (and there is no voltage present at the input pins for the anti-trap at the module and the module earths are good) then whatever controls the function in the module isn't working. Be it some sort of transistor or timed relay that is switched off when the window is fully up/down and hence tripping the switches located in the window regulator.

I think there may be another factor in the form of some sort of software in the module, I wasn't able to test this as the owner got impatient and tried a module before I could check with my friend the former BMW tech. Still, it worked out o.k., hopefully the keys work by now - not my problem!.

MatteH Oxford · 23 Aug 2013 at 16:21

Ah, not all Z4s have one touch passenger side... I think? This one does but it is a Mcar coupe.