I left my car garaged over the very cold winter. When I eventually tried to start the vehicle the infra red key fob would not open the central locking to disarm the immobiliser. There was also no power to any components except the lights. I replaced the car battery but to no avail. The key fob still does not open the central locking or disarm the immobiliser. I changed the battery in the key fob but to no avail. I am at a loss to why the key fob or the car battery do not work. Any suggestions would be appreciated.

Quit SHOUTING will ya :>D Typing in all CAPS is considered SHOUTING in Internet land. It also make the text VERY HARD TO READ.

You need a good, local auto electrician with a pro-grade scan tool computer. You have a faulty module probably Body Control Module, or Security System Module, the sensors and receivers connected to them, or a general communication issue.

If the key had gone faulty, the key code must be re programmed on the vehicle computer. This can be done only using a PIWIS tool, available at the dealer or at a qualified Porche garage.
Try also the following reset:
turn ignition on,
turn off.
remove the transponder from the column
push any button on the fob within 6 seconds.
This procedure will reset the key synchronizing again with the vehicle computer.

sadly I must tell you this forum is answered by mostly old DIYER"s and do not know every trick about every problem that the world has , so suggest only you see a dealer locally of your Make of vehicle. it could be as simple as the bcm needs reprogrammed .which only dealers can do

Check with your Ford garage if its a fob that contains a miniature battery that has died on you.

Same issue here, Sonata 2011 GLS and no key found (but more and more often at winter time) At dealership they said....its 100% computer problem, we can change it for $900 but we dont guarantee it will work normal again. Replaced 2032 battery 3 times made no difference so i thought its a power issue somewhere. i left my car on parking for 2 days for test. Opened door and saw it again...key not found. I connected a booster cable from running car to battery and left it for 10 min to charge. AFter 10 min i had a surprise...key found and car started easily. So its the Hyundai Factory car power design issue. Now i need to change my alternator to cover my theory. thx. ___

It could be the frequency amplifier problem. The AM radio may not work too. Check the fuse first to see if it is just fuse problem. Otherwise the frequency amplifier can cost you $1000.

if you got the FOB really wet then the circuit board is ruined, you are going to have to replace it.

The remote should be built into the key. If not the remote central locking would be after-market. After-market remote central locking is part of an anti theft device so the fob you get with the key's has two function's it opens the door and disables the imobliser. If it had a fob and it was'nt with the key's then the ignition would'nt work so the car would'nt start. So it dosent have remote locking. Before giving up check the dash and suround's for a small either green or red light which looks like it was installed after-market if their is one then it still may have remote locking but was disabled for some reason but although it is there unless you really need it don't bother with it because you will need to get it rewired then get a fob which will need to be programed. Hope this help's Cheer's

if your unlocking the doors with a key and the engine is starting it wont have a key fob,if your opening the doors with the key and the alarms going off and it wont start then it will have a key fob

immob fitted as standard,coded key so it wont start with wrong key or shorted ignition alarm fitted as standard too,is it controled by an infa red key fob for central locking or just a key