6C Key Fob Battery Change/Resync

[rbz5416]

I left my spare key with the garage yesterday while they worked on the car. on picking it up, they advised that it wasn't operating remotely. A quick Google showed how to change the battery but I thought it odd, as the spare key is hardly ever used & the main key is still on its original battery. So changed the battery but still nothing. Swapped the battery with the good key just to be sure but still nothing. Tried re-pairing but still nothing.

My question is for anyone who has changed a dead battery & then needed to resync. After changing the battery & before resyncing, does the red LED on the fob flash with a key press? Mine doesn't which suggests it's dead but not sure if the LED only becomes active once paired.

[iichel]

the red LED is always lighting up upon key press

[rbz5416]

the red LED is always lighting up upon key press

Thanks, but not what I wanted to hear!

Struggling to understand how it died just hanging on a hook. Now do I butcher it or, as it only gets used for servicing/MOT, leave it alone & let the next owner worry about it...

[iichel]

It might be worthwhile just to clean the contacts for the battery.

[rbz5416]

It might be worthwhile just to clean the contacts for the battery.

Good call but I did that when I changed the battery.

[TrebleTA]

Resync put key in start car turn off. Put key in door turn and hold windows will drop. Turn other way windows close. Should be now be all synced. I think.

P.s batt will die over time, why they have a expiration date.

[rbz5416]

Resync put key in start car turn off. Put key in door turn and hold windows will drop. Turn other way windows close. Should be now be all synced. I think.

That's not what the manual says. But in any case, resyncing a dead remote is a lost cause. That's why I was seeking clarification of the LED behaviour.

P.s batt will die over time, why they have a expiration date.

Indeed, but both fobs are on their original 6+ year old batteries. The one in this dead fob still measures over 3V.

[TrebleTA]

Well I have to do the door key trick so I can hold the button on the fob to open the windows,
If the batt has a charge yet not working check the batt fob pins to pcb board. On my golf the pin needed a solder, Else guess key is nackered some how, maybe the garage did it by mistake drove over the key am guessing here but has been knowen.

[rbz5416]

This is the procedure for operating the windows from the fob:

https://www.uk-polos.net/viewtopic.php?p=575917#p575917

Sadly the fob is sealed & requires cutting open to access the PCB, which is a bit too drastic for a spare.