I wanted to know if any members had a Air Mix Door Motor/Actuator for sale for a 1991 Infiniti Q45? My heater isn't working and I think that this may be the problem. Thanks for everyone's time in reading this topic. Please let me know cause I'm having trouble finding a replacement.

Do you have a part number you could provide us?

I tried looking at this extensive catalog, but it seems some parts that looked like they would be relevant are not available any more:
https://www.infinitipartsdeal.com/parts ... am=270_001
Maybe this one? 27741-60U00. I didn't find any relevant pictures in my online search though.
Some other older Nissan might share it.

Also, why do you think it's the issue? Does it not respond when you juice it, say from a car battery?
Since you have removed it (assumption), can you manually force the blend door to either end to see if you get heat then?

This would be the first failure I've heard of on the earlier Q. Some of the later models had mix door hinge failure, but nothing like that on the 90-93 that I can remember. Of course at 27 years old, everything is fair game.

There is a ton of information in the FSM about testing the actuators, and a self test procedure available as well. The self test starts on HA-65. On HA-87 there's a good breakdown of where the motors are located. It looks like there are three - Intake Door, Air Mix Door, and Mode Door.

https://parts.infinitiusa.com/nissanpar ... Filter=270

HEATER & BLOWER UNIT - ACTUATOR-AIR INTAKE BOX
Part Code: 27080
Part Number: 2774060U00
Year range 7/1990 to Present
Quantity per vehicle: 1
*MSRP: $162.20
Fits vehicle filters:
( BODY = 'FEDS' )
or ( BODY = 'CALS' ) CHECK ONLINE PRICE

HEATER & BLOWER UNIT - ACTUATOR ASSY-MODE
Part Code: 27733M
Part Number: 2774160U00
Year range 7/1990 to Present
Quantity per vehicle: 1
*MSRP: $202.18
Fits vehicle filters:
( BODY = 'FEDS' )
or ( BODY = 'CALS' ) CHECK ONLINE PRICE

HEATER & BLOWER UNIT - ACTUATOR ASSY-AIR MIX
Part Code: 27733N
Part Number: 2774260U00
Year range 7/1990 to Present
Quantity per vehicle: 1
*MSRP: $184.82
Fits vehicle filters:
( BODY = 'FEDS' )
or ( BODY = 'CALS' )

I think I just had an air mix door or motor failure. It blows extremely hot air when the temp is set on 65. I see a lot of air mix door failures on 4th gen Maximas and I30s. Actually, I have a 4th gen spare for those knowing they eventually fail. I'll be looking into the self-test information.

Ha, don’t despair! I just did my airmix motor (again) today. Last week, I got it to work by unplugging and moving the hinges around. Worked (noisely) for a week. Was fed up with the wasted time. Ordered a new one from infinitipartsdeals above, came in yesterday. The first time, I took 2 hours trying to get it off/on. This time, I didn’t bother removing anything on the dashboard. Just reached right under there and did it all in 45 minutes.

maybe try to open it up and see if there’s something you can re-lube. Clean the hinges of the doors best as possible. I didn’t open mine up, but It looks very easy to open. I’m actually going to open mine tomorrow to see whether I wasted money buying this s*** or not.

I bought it new this time because I can’t afford to almost get frostbite like I did earlier this year. Had I know the s*** was right under my feet...I’ve of done it sooner!

I never had this problem with any car. I think the previous owners had kids (judging by the gunk between the seats I had to scrub out today...bad a** kids). They probably played with it and burnt it out. I have a 97 Maxima that hasn’t ever had that issue and simply has a manual sliding temp adjuster.

OwnerCS wrote: ↑

Tue Mar 27, 2018 5:58 am

I think I just had an air mix door or motor failure. It blows extremely hot air when the temp is set on 65. I see a lot of air mix door failures on 4th gen Maximas and I30s. Actually, I have a 4th gen spare for those knowing they eventually fail. I'll be looking into the self-test information.

Mine was blowing ambient air, then it conked out in the hot position. I had to leave it in recirculate until my new one came in. It just means the flue was left wide open. You may can look under to the right of the gas pedal to see if u can lift the arms off the hinges and manually close it.

mac, my Hi-Lo vent motor "seized" ,plastic gear, driven by worm-gear motor(motor tough!).High heat caused the different types of plastic to cause the circular "driven" gear to freeze on shaft - cover "cracks open" , all it took was opening up it's I.D. , "sloppy " enough to jam beaucoup Lith grease all around and I saved the $95 dollar cost of a rare part by the way , only "Used" was out there ( a gamble that used part has same problem ) Been 3 years still works - no "sticking" & no more "coffin opening sound" when changing Vent / Hi-Lo.I just left underdash open two weeks to make sure of the FIX. G 3/30/2018