SamL11B

Hey gang, I’m in need of some help as i’m on disability and live in Phoenix, AZ, USA and my 08 G37S’ AC has stopped working and I’m trying to figure what went bad. I know the compressor is still good because when I set the AC to fresh air, I can feel refrigerated air being forced through when I drive. Also, when I tyrn the AC off and then turn it back on, I hear an audible click as if a switch or relay was tripped, then if I do that with my ear near the back of the glovebox compartment I can hear a dull whining like a gear is moving or something both when I turn the climate control off and on, but but nothing else happens. The blower motor is probably still good as o replaced it with a new one last summer. Also, for a while the motor would intermittently kick on and function normally until shut my car off again. Then eventually it just stopped turning on at all. If I was a betting man, I’d wager the fault lies between the power switch on the head unit and the Blower motor, but I haven’t a clue what parts are between those and or what the likely suspect is.

Thanks in advance.

ILM-NC G37S

iTrader: (3)

The blower is either working, dying, or dead. There is no "probably good." Just because you replaced it once does not automatically assume this unit is working.

1) What happens when you manually adjust fan speed?
1a) Does air output match speed?
2) What was the original reason you replaced the blower last year? OEM unit or some aftermarket knockoff?
3) Have you physically checked the blower? Does it turn freely by hand? Connector clean and tight? Any signs of dirt or water damage?
3a) Do you have a multimeter? Good 12V+ and ground?
4) Is your cabin air filter dry and/or does it show signs of water damage? Water is known to leak past the windshield cowl and flood the blower motor housing causing issues. This is becoming more common as these cars age.
Thankfully, I am not a betting man. Everything you described points to the blower motor being suspect. If you have good power and ground then that is the issue. If not, then you can investigate further upstream.
All those clicking and "whirring" noises you hear are the different relays cycling as well as the blend door motors (air direction and temperature) being adjusted by the ECU/AC amp- all normal sounds.

SamL11B

]The blower is either working, dying, or dead. There is no "probably good." Just because you replaced it once does not automatically assume this unit is working.

1) What happens when you manually adjust fan speed? ***nothing***
1a) Does air output match speed? *** no flow at any speed***
2) What was the original reason you replaced the blower last year? OEM unit or some aftermarket knockoff? *** OEM bearings failed***
3) Have you physically checked the blower? Does it turn freely by hand? Connector clean and tight? Any signs of dirt or water damage? ***spins the same as when I first bought it**
3a) Do you have a multimeter? Good 12V+ and ground? I don’t have one.
4) Is your cabin air filter dry and/or does it show signs of water damage? Water is known to leak past the windshield cowl and flood the blower motor housing causing issues. This is becoming more common as these cars age. ***dry as a bone, no signs of water spots**

also, fuses 21 and 22 on the driver’s side panel are good.

regardless: I just unintentionally confirmed the blower motor works. I unplugged it and plugged it back in while the car was on, seconds later it kicked on. I turn my car off and back on, nothing. Correct me if I’m wrong, but does that not guarantee it’s something electrical?

13_SkylineSedan

Isn't there also a blower relay on the back side of the in-cabin fusebox? Could that be failing?

ILM-NC G37S

iTrader: (3)

Could definitely be a sticking/ failing relay though I wouldn't rule out the blower motor either. Blower needs three (3) items to run:
1) power (12V+),
2) ground, and
3) control signal from the amp.

Without a multimeter- or having a reputable mechanic check things out- unfortunately, you will just be throwing parts at the problem.

Bpstorm

if the blower motor does not come on then you need to check the power transistor. Very common to go out. Make sure all fuses are good first.

ILM-NC G37S

iTrader: (3)

These cars do not use a "blower resistor" like in the old days. Everything is incorporated into the blower motor.