Q: Tata Indigo (2007)

I own a Tata Indigo (2007) and lost FOB key. In one of the keys I've got when I bought the car (brand new) there's a 4-digit code printed on a piece of plastic. I was wondering if it is a system like, i.e., Land Rover's EKA. What I don't know if it's the same procedure, or if there's some "trick" to start entering the code -i.e. to open and close the driver's door first-, or in which lock I gotta enter the code, or what direction I should turn the key the first time, etcetera. I can't find anything anywhere. Gotta disable the immobilizer, and shops in my area are trying to make me change the whole ECU and centralized lock. (Can't afford that at all, it's over 1000$)

Thank you in advance.