depends how good you are at soldering
most ecus have the chip soldered onto the pcb, you need to be very careful in removing the old chip as you don't want to lift or damage any of the tracks on the pcb or damage any other components.
I fitted a socket to my ecu so i can swap chips in about 5 minutes, ecu out, case apart, old chip out, new chip in, do up case, put back in car.
the number under siemens is what you need to give pennyduck including the letter at the end - the letter indicates which revision the ecu is at
the C in this case means the immob circuit is included on the ecu board and not a seperate board usually hidden in a box under the centre console or behind the heater . this ecu is a pain in the arse to mod but mick can provide a chip for it, the C revision did not last long, the most common i have seen are B and D
here are the guts of the ecu
thats the chip that needs to be desoldered and replaced (always use a socket so its easy to change back to your original chip if needed)
this is why you have to be careful - surface mount resistors and capacitors on the underside where the chip sits, apply too much heat and those will simply fall off
Original chip out
new chip in
it can only be fitted ONE way
notice on the pic with the chip removed, the diagram underneath it shows a semi circle on the left hand side, the chip also has a little semi circle cut into one end, so semi circle over semi circle
when you have soldered the socket in, nick your other halfs nail polish and lacquer all the solder joints, this will seal those joints from water preventing corrorsion
Job done, now do up the case and whack it back in the car
on C revision, the ecu now needs to be reset
with bonnet, doors, boot SHUT, use your remote to plip the doors locked and then plip them unlocked, thats reset the ecu and immob on c revision
