Huge Starting Problem!

[rhos liverpool]

Hi all

new to this...

right where to start,the other half was driving my is200 99/00 navi crashed (nothing major) took the back wheel out and back door and a bit of sill (lost control on oil patch not used to driving rear wheel drive cars) this was 3 years ago i have a few cars so this was left in one of my warehouses awating repair i have now got round to having it fixed a bit of welding here,new wish bone,door etc the cars Battery went flat...

we have now come to starting the car and had no luck

i have had the world and his wife look at this car the problem is the car will lock/unlock off the key all light/raido work all the boxes are ticked for the car to do as it should BUT the car go's to turns over as it should but wont fire up the security light on the dash flashes away all of the time (even when the key is in the barrle) (unless i arm the alarm then it stays on for 50/60 seconds and then flashes as it should i have had:

new Battery in car and key

had an auto elec look at the fuses (not the best auto elec in the world)

had the ecu flashed/reprogramed/then virginated???

then got a 2nd ecu incase the old one was damaged?? and did all the above to this one

new key programed into the ecu and am sure there is 1 or 2 other things

but nothing changed i have put quite a bit of money into this now and dont just want to give up on it the car is like brand new again but this problem is realy begining to get under my skin any one got any ideas??

i am thinking of immobilizer module/fuse i have a beginer level knowledge of cars but nothing major dont realy want to put it into the stealers for them to want to put another ecu in to it