[SSN]

fyi (bmw x3 G01) I recently have had the emergency call system not available message appear at the bottom of the Speedo. As most posts have suggested to replace the TCU battery as this tends to be problem. I purchased the battery from the dealers and replaced myself as they overcharge and make out it’s a bigger job than it actually is. However on this occasion it did not solve the issue - after investigating further myself I can see corrosion on the TCU unit which seems to penetrate from the shark fin. It’s clearly an issue which is becoming more common on BMWs around 4years old onwards. As the car is out of warranty BMW quoted just shy of £2k to replace. I spoke with a specialist they have quoted just under £900 (the TCU cost around £750 from BMW and has to be ordered specifically for the vehicle with VIN details etc then will still need programming). For now I have just asked him to deactivate the TCU which has cleared the error message on the speedo (cost me £130). This still leave me now with no SOS function/no BMW notifications to the vehicle virtually/no BMW phone app for tracking and remote features to the car. I just wanted to share my experience for other BMW Owners

[Jonnyt]

Water ingress through the shark fin does seem to be a common issue across a range of models. I recently had to have the TCB module replaced on my 2019 X3. It was still under the approved used warranty, but they wouldn't cover it in full, the best I got was them covering 100% of parts cost and 20% labour, still cost me over £700.

[BMWZ4]

Doesn't solve your current issue, but why not put a bead of silicone around the shark fin...