Battery Memory savers

[Tammma]

Hteepee

I reckon the key must communicate the key battery voltage back to the car...has to be.

T

[hteepee]

I wondered the same, but don't see how. I don't see how age of battery is how it works (2nd battery fob lives in house unused, but worked when first fob failed). Total mystery, but so long as swapping battery clears message on infotainment screen and continues to operate central locking then that will have to do I guess.

[Blackstar]

I wondered the same, but don't see how. I don't see how age of battery is how it works (2nd battery fob lives in house unused, but worked when first fob failed). Total mystery, but so long as swapping battery clears message on infotainment screen and continues to operate central locking then that will have to do I guess.

Mine came up with the change key fob battery message last week each time I started the car. Just to check on the process before I had access to a replacement, I removed the old battery and then put it straight back in. The message then cleared and stayed away, didn't come back even after several days before I was able to fit a new battery. When I checked the old battery it was coming up as 95% full on the tester. So I guess it can't be based on actual condition - maybe length of time since last changed or else number of times used?

[Tubemonster]

Carista showed up a fault code on mine No/.204546 which said "Remote Key 2- current too low" I replaced the battery and it hasn't come back.

[mrew42]

I wondered the same, but don't see how. I don't see how age of battery is how it works (2nd battery fob lives in house unused, but worked when first fob failed). Total mystery, but so long as swapping battery clears message on infotainment screen and continues to operate central locking then that will have to do I guess.

Mine came up with the change key fob battery message last week each time I started the car. Just to check on the process before I had access to a replacement, I removed the old battery and then put it straight back in. The message then cleared and stayed away, didn't come back even after several days before I was able to fit a new battery. When I checked the old battery it was coming up as 95% full on the tester. So I guess it can't be based on actual condition - maybe length of time since last changed or else number of times used?

Could be dirty/corroded contacts and taking it out and replacing it was enough to clean it. Bit like when the old TV remote starts playing up so you remove the back and rotate the AAAs and hey presto it works again

[Blackstar]

I wondered the same, but don't see how. I don't see how age of battery is how it works (2nd battery fob lives in house unused, but worked when first fob failed). Total mystery, but so long as swapping battery clears message on infotainment screen and continues to operate central locking then that will have to do I guess.

Mine came up with the change key fob battery message last week each time I started the car. Just to check on the process before I had access to a replacement, I removed the old battery and then put it straight back in. The message then cleared and stayed away, didn't come back even after several days before I was able to fit a new battery. When I checked the old battery it was coming up as 95% full on the tester. So I guess it can't be based on actual condition - maybe length of time since last changed or else number of times used?

Could be dirty/corroded contacts and taking it out and replacing it was enough to clean it. Bit like when the old TV remote starts playing up so you remove the back and rotate the AAAs and hey presto it works again

That is very possible. I did also wonder about the cold weather as where the key is kept is in part of the house that isn't always heated. Anyway, for the sake of the cost of a battery I've left the new one in and also put a spare new battery in the glovebox in case the other fob goes.
Interesting to see that the OBD does actually sense the battery current.

[Rory]

I wondered the same, but don't see how. I don't see how age of battery is how it works (2nd battery fob lives in house unused, but worked when first fob failed). Total mystery, but so long as swapping battery clears message on infotainment screen and continues to operate central locking then that will have to do I guess.

Mine came up with the change key fob battery message last week each time I started the car. Just to check on the process before I had access to a replacement, I removed the old battery and then put it straight back in. The message then cleared and stayed away, didn't come back even after several days before I was able to fit a new battery. When I checked the old battery it was coming up as 95% full on the tester. So I guess it can't be based on actual condition - maybe length of time since last changed or else number of times used?

It came up on daughter's SEAT Ateca (so I'm assuming same system) 3 mths after the dealer changed the key battery. Actually I say "came up" - she hadn't seen the warning at all because with keyless start you don't see it (or maybe it's there extremely briefly). It's only when I turned the ignition on (by trying to start the car without clutch depressed) did the warning become obvious. Seems a poorly thought out way of warning.

So it looks like it is checking the battery condition. Not unheard of - other daughter had a Mitsubishi Colt and that flashed the indicators like mad on unlocking when the key battery was low - didn't know what the heck was going on first time it did it.