fix a faulty immobiliser?

My immobiliser is preventing me starting my car..how do I locate and disable it? The vehicle is a Vauxhall Frontera 1995 (M Reg)model.

The car stopped when driving along and now won't start at all...it is definitely an immobiliser fault
The red light near the key is on all the time,it should be on and off.

Thank you in advance for your help
07833998184