Z4 2003 E85 Central Locking

[mixtli]

Hi guys,

My key fob does nothing! About 3 weeks ago, I jump started my Z4 on the battery as I stupidly let it go flat. Everthing returned to normal except the central locking. Pressing they key fob illicits no reaction from the car. No beep, no lock activation / deactivation, no flashing indicators. The only way into the car is with the key through the driver's door then pressing the door unlock button inside the car to unlock the passenger's door. It's as if the fob is either completely dead (unlikely) or the car no longer recognises / reacts to it. The GM5 module was the first suspect so I sent if off and 2 faulty relays were replaced. Now things seem better opening off the key in the drivers door lock (even the fuel filler cap unlocks which I'm not sure it did before - long story but not relevant here) but still no response from the fob.
I've recharged the key fob by taking the car for a long drive and also charging it on a toothbrush charger but still nothing. I suspect that something went 'pop' when I jump started it as everything was fine before this. I am tempted to get a replacement mirror as the receiver is in there, I think and follow some online guides to pair the key to the replacement receiver. Does anyone think this might be a good idea or am I heading down a deep fruitless rabbit hole? Any suggestions would be very welcome as it's driving me mad.

Thanks!!

[Aloyouis2]

Try this!

https://www.zpost.com/forums/showpos...&postcount=127

[Piper1]

Also if you haven’t yet when batteries loose charge, even dropping below voltage but not entirely flat codes and gremlins have a tendency to surface. Code read it and clear anything that comes up if you haven’t.

[mixtli]

Hi. Yes. I've tried that (again today) and many other reprogramming procedures without any success. It is completely unresponsive but the car starts and drives without a problem. I have only one key, unfortunately so can't 100% rule the fob out though I don't think it's where the fault lies.

I think there is 3 parts to this system?

1. The fob transmits a signal
2. The receiver in the rear view mirror receives the signal
3. The GM5 module carries out the 'instruction'. Unlock the doors, enable/disable the alarm etc.

Does this sound right?

[mixtli]

All codes were cleared about a week ago.