Both fobs has stopped working - E90

[Ciaran]

Strangely both of my fobs have stopped opening my car - I can still start the car with them after I manually open with the removable key. I've checked the fuses but they seem to be ok. The central locking also works fine when driving off. Any ideas?

Thanks

[BFleming]

The Diversity Amplifier sounds suspect. Does any of this sound familiar? https://www.pistonheads.com/gassing/topic.asp?h=0&... People confuse things with the E90 & E91, but they're very different.
This might help: https://www.realoem.com/bmw/enUS/showparts?id=VB33...

Edited by BFleming on Wednesday 8th January 12:03

[Ciaran]

Thanks

Internal door lock button works, no issue wth radio. I'll have a look for one of those diversity antenna things online.

[BFleming]

Ciaran said:

Thanks

Internal door lock button works, no issue wth radio. I'll have a look for one of those diversity antenna things online.

The advice seems to be 'stick to a similar year to yours'. Not sure how you'd know, as a part number is a part number. Anyhow, keep us posted.

[Ciaran]

Will do. There seems to be a few on ebay so I'll give one a go.

[PTF]

Had this on an E91.

The diversity antenna has a design flaw. Moisture gets in and the circuit board corrodes. BMW have a bulletin for this so when they replace one they are supposed to seal the unit with some silicone sealant, yet strangely they won't replace these for free despite the design flaw!

BMW wanted 2 hrs labour to do mine after they investigated the cause of the issue. I paid £100 for diagnosis expecting it to be covered under warranty, but it wasn't because it doesn't cover water ingress. In the end i bought the part new off ebay and fitted it myself in 1/2 hr.

[BFleming]

PTF said:

Had this on an E91.

The diversity antenna has a design flaw. Moisture gets in and the circuit board corrodes. BMW have a bulletin for this so when they replace one they are supposed to seal the unit with some silicone sealant, yet strangely they won't replace these for free despite the design flaw!

On the E91 it's mounted in the upper part of the hatch, under the 'spoiler'. Moisture gets in as you say, but also the wiring loom between the car body & the hatch frays over time & you lose functionality.
On the E90 though, it's under the roof next to the high level brake light.

[BobSaunders]

Appreciate not a E90. But, my E91 currently has the same issue, however it is a broken wire issue in the wiring from the diversity amp into the car. Needs splitting of the sleeving and testing of wires and replacement of said wire - just incase the diversity amp change does not work.