I bought a Maxima last march. My friend put a motor in it, and we couldn't get the car to start. Last week I had the car towed to the dealer where they told me the ecu was bad and wasn't firing 4 of the coils. I took a look at all the wiring on the coils and check all of them and I noticed that the one coil on the front drivers side of the engine closest to the tranny (cyl # 6) the plug was messed up. When I on plugged the plug from the coil all three wires came out of the plug. Anyone have a picture of where the wires go on the coil? I know the center wire is ground, and I believe the back wire is the red wire, and the one on the front of the coil is the grey/red wire. If anyone could help here I would appricate this. I ended up replacing the ECM with a used one, and still the car won't fire. Dealer stated that ECM had code 505, and stated that IACV motor was bad. I wonder if the used ECM I got was bad. The original ECM I took out of the car and opened it up. Upon opening the ECM up, it was in perfect condition with no burnt chips. The used ECM I opened it up, and I found that the STA509A chip was burnt up. Kind of funny that we had no codes on original ECM, but after installation of used ECM dealer found code 505 and couldn't get car to start. I ordered a new chip, common problem, read several posts about IACV motor. Replaced IACV motor. Hope to get this POS running.

 

look at one of the other coils. All coils have a red and black wire going to them (12 volts and ground) The third wire is a different color on all six and is from the ECM and is the signal to fire. Match the red and black wires with the other coil packs and the third wire goes in the remaining hole.

 

Look up the wiring diagram in the fsm. They have every wire and which pin it goes to in the connector.