Hello guys, I have a 2004 G35-Coupe Standard. I recently bought it with body damage, so I used to jump start the car all the time with a jumper while it was in the mechanic shop and one of the battery cables were loose. NOW THE CAR IS NOT STARTING AT ALL!!! I HAD A MECHANIC CHECK EVERYTHING, EVEN CHANGED THE SPARK PLUGS. HE SAID ITS THE ECU THATS MESSED UP BECAUSE THE ENGINE LIGHT ISNT EVEN COMING UP WHEN YOU PUT THE CAR ON IGNITION (ON)... PLEASE CAN ANYONE HELP ME WITH THIS? DOES THE SERIAL NUMBER ON THE BACK OF THE ECU HAVE TO MATCH THE ONE IM REPLACING???