its not my car but a customers, its a 2011 maxima they brought in with a used compressor for me to install. I verified there was power and ground going to the coil and replaced the compressor, drier and expansion block. 2 weeks later it came back with the coil open again, still had good power and ground to the coil. The customer got a new compressor and we installed it, AC was ice cold after and lasted about another 2 weeks and now its back with the coil burned out again. The customer knows a guy at the stealership and he said the pulley might be bad but im not so sure....3 in a row? no way, it has to be something external but the only thing I can think of is a problem with the voltage going in. In my experience all AC coils take straight power from the electrical system and not a reduced voltage.....is this the case with the maximas? im in uncharted waters on this car so if anyone has any ideas im open to suggestions.

 

Yup. You are correct. Pressing A/C button on these cars signals the HVAC control unit to energize the relay in the IPDM E/R (independent power distribution module engine room) which feeds 12V to magnet clutch on compressor. You can disconnect the connector at compressor and with IGN ON, turn on A/C button and check voltage is 12V. Also verify no continuity to ground with IGN OFF.

Does this Maxima have Navi, or just the monitor package with rear backup camera or base model with basic orange small display? If it has Navi or the monitor package, there is a diagnostic you can get into that will tell any error codes in HVAC system. Might very well get you moving in a direction.

Also there is an auto-active test that will test several things including A/C clutch operation. It is designed to test the IPDM E/R. Turn IGN ON, press door jamb switch 10 times quickly, turn IGN OFF and then turn IGN ON. It goes through a series of tests, one of which is energizing/de-energizing A/C clutch 5 times in 5 seconds....whole test repeats itself 3 times. Engine not running so you may be able to pick up on something you wouldnt normally with it running.

However I agree. Sounds like voltage spike due to improper ground or poor connection on power side. Have you checked the relay in any way? If it isnt making good continuous connection, it would certainly cause voltage spikes...just a thought.

 

Also found this in the factory service manual:

Check magnet coil for a loose connection or cracked insulation...

Center bolt torque is 9 ft-lbs.

Clutch disc to pulley clearance is 0.3-0.6mm (0.012 - 0.024 in)

When replacing compressor clutch assembly, always perform break-in procedure. This is done by engaging and disengaging the clutch about 30 times. Break-in operation raises the amount of transmitted torque.

Dunno how any of this would cause the coil to burn out other than loose connection or cracked insulation above, but it's there FYI...

 

good info...I see the relay in the schematic but the fuse/relay box has no such relay labeled...Mitchell has no legend and I was unable to find any online(look up 2011 maxima and get crap for altimas all day long...thanks Google)im beginning to suspect its a built in relay like ive seen on other cars.

 

Have you tried reviewing the actual Nissan FSM for the maxima? You can find it online at the below link through NICO Club. Might be a better reference than Mitchell or anything else you have seen.

http://www.nicoclub.com/archives/use...-database.html

S