Intermittent no crank no start

[AV8R4AA]

This post is for my 4.6 E53. One of my ignition keys will be fine for several months. Then out of the blue will fail. Causing a no crank no start condition. Pull the key out, hum a Rolling Stones jingle, retry.
Starts second time. Until recently. The key just won’t start the X5, consistently.

I have since switched to my back up key. Works perfectly every time.
So I feel I have a wonky key. Since one key works perfectly and the other is
iffy. I don’t exactly know what to do. Both keys have good battery and Fobs work fine.
Now what?

[andrewwynn]

Indication is a bad solder joint on the RFID circuit.

Reflow the circuit board is the normal fix.


–awr–

Using Tapatalk VIP on iPhone

[AV8R4AA]

I know how to do that.

TY

[Clockwork]

I was chasing this problem for years. It wasn't bad at first but then both keys stopped and I was having this issue about 2 times a day. Finally ended up having the Module responsible for security cloned and replaced/installed.... Fixed my issue.

Sent from my Pixel 6 using Tapatalk