I have just started a new job, would have been my third day today, go to the car at 6am in Morning(-6c) in the Snow and 'oh great car won't open' I open be car with the key but the engine won't start as the immobiliser is still on, I walk back to the house which is up the house due to lack of parking, take the spare key and fob, battery flat in that one too. I know there is a pad in the glove box but I have no clue how to use It or the cold, I now have some new battery's but they are different in each fob, I have tried using the same number ones but I can't get one to start working, tho it was really faintly this morning,
Does anyone know the correct battery's needed and the correct order?

 

What model and year car? .

 

The alarm should have gone off when you opened the door with the key (may be model dependant?) You then need to cancel it by entering the code into the pad. You then have a short period of time to start the car. You should have been told the code when you got the car! Chances are the guy you got it from didn't know it either?
JohnD

 

Is it possible your car battery is flat?

 

Cold kills battery's if they are weak
& as your alarm wasn't activated on door opening
My guess also is , your car battery is dead , not your keys

 

Most likely car battery flat, however,

Not wishing to slag the OP off, but it's amazing, given the number of posts/threads on here regarding re-coding key fobs and renewing the alarm pin, that people who use this BB, still drive around not knowing how to setup the alarm.

At least the OP knew where the keypad was, unfortunately hasn't done anything about the code............................

The separate Fob uses 2 x CR2025 batteries whereas the key type uses 1 x CR1620.

As far as I remember the +ve and -ve are marked on the casing/pcb

 

There is a thread on how to set the code up , wether you know the old one or not. Change it to something you will remember , and you wont have the problem when the key stops working.