Maruti A-star (Petrol Variant) sold in India has an ECM from Denso. The pictures shown above is for 2010 model Maruti A-Star ECM. It is sealed in a sturdy plastic box and is mounted in Engine compartment near the battery.
Opening the ECM
Opening the plastic casing is bit risky as there are plastic locks on this ECM box which tends to break even with force required to open this casing but don't worry as you can always use an quick-drying adhesive when fitting ECM chip back into box. Try to save as many locks as possible, it will help in fitting the ECM
Fitting the Chip back into box
Chip can be easily slided back into casing but when you'll try to lock it with outer casing, it will not fit. Here is the trick, before sliding the chip back into casing see carefully into plastic lid attached to the chip. There is a gasket which needs to be removed first and fit into the other half of plastic casing. Then it will slide and fit comfortably.
Immobiliser codes are stored in 9356 EEPROM visible in fourth photograph in above slider.
Opening the ECM may void the warranty of Car. ECM is a very sensitive component and may even get damaged through static electricity. Always handle the ECM carefully in a dust free and static free environment.