One of my keyfobs has decided to stop working, it will no longer arm or disarm the vehicle. Whenever the button on the keyfob is depressed the LED on the keyfob flashes three times and that's it.
Anyone any ideas what this is and what causes it?

 

Have you tried new batteries? The LED takes very little power to illuminate it, but the transmission of the code takes much more.
The LED illuminating is not an indication of a good battery.
When chaging the batteries, slide the cells out from beneath the spirral contact, be careful not to bend the contact out of the way as it can be broken off the circuit board if care is not taken.
The remote does not require any re-programming after changing the batteries, so should continue to work again if it is the battery at fault.
SS

 

I've tried replacing batteries, has no effect, it still won't work.
Can't understand why it's working fine one minute and then stops the next.

 

OK, so thats the batteries out of the equation!

Does the remote in question start working again as suddenly as it stops?
It may be a a case of Radio Lock Out rather than a faulty remote. How old is the vehicle/alarm system?

SS

 

The remote in question stopped working a couple of days ago and hasn't worked since.
I have two keyfobs of which both were working fine, one has stopped working but the other continues to work without any problems, arming and disarming the vehicle. This would suggest the alarm/immobiliser on the vehicle is working fine and it's just a problem with the one remote.

 

Yep, I would agree.
I've not heard of such a problem before though, either they work or they don't - never had them "drop a code" as this one appears to.
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