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03 M45 ECU Difficulties
Posted to Technical Discussion Forum on 11/15/2012 11 Replies

Hello Everybody, a few weeks ago we got an 03 m45 in , customer complained of it running rough. G.S. guy got ahold of it and replaced spark plugs and attempted to replace coils, still ran rough. Our shop foreman got on it and found that the ecm was not firing several of the coils and determined that the ecu was bad, so he ordered a used one and sent it down to infiniti so they could install it/ program it. Unfortunately the vehicle would not start at all with a new ECU and would not take programming. So now I have inherited this problem. With the original ECU it starts and runs on 3 cylinders. Toss in another one and it just cranks. I personally believe it is an immobilizer issue and I've only got communication with the NATS and nothing else. All of the powers and grounds are there on the ecu and the can lines check out with 60 ohms in between. We have a j2534 so if necessary we can try programming it ourselves. Unfortunately due to lack of info on alldata,direct hit, and around the internet I have no idea what I need to do. If somebody could point me in the right direction it would be greatly appreciated especially since the techs at infiniti couldn't even figure it out

Roderick Schmidt
Complete Automotive
Glen Allen, Virginia, USA

11 Replies Received (View Replies)


car Vehicle Data

2003 Infiniti M45 4.5L

Engine4.5 L
Trans5-speed Automatic (Electronic)