Remote Locking Help Needed

[BATMAN1]

Hi,

First post so here goes..

I have a 2002 corolla terra 5 dr H/B and when I bought it it had remote locking. No flashing indicators or alarm, just the basic central locking.

The button was not on the key itself but on a seperate rectangular black fob with a red outline on the button. One button to lock/unlock. No name or brand on the fob.

A year or so ago it stopped working and despite changing fob batteries etc , no joy. Asked about it at a main dealer and he said he would replace the control unit for 150 squids!! Following that someone told me it was a relatively easy job to fit such a unit myself.

I have now come to the point where I would like to change it and I have a couple of questions which I hope someone here can help me with, rather than pay through the nose for it at a dealer.

1. I cannot find where the control box might be fitted and what it looks like. I don't want to pull something out that may cause other problems. Can anyone tell me where it most likely is and what it would look like?

2. When I do locate the box, could I purchase a unit on eBay or somewhere and just replace the existing unit by unplugging it and plugging a replacement on in it's place?

Any info is much appreciated.