maximagasm

99 max SE w/ the electronic HVAC controls. Blower motor works correctly at all speeds and everything electronic appears normal but all I get is HOT air. Regardless of outside temp and regardless of settings on the panel, I am getting super hot air. Even when the heater is hut completely off and the blower fan isnt running at all I'm having to roll down the windows in 55 degree weather to keep from roasting to death. The searching I've done talks about the blend door, blend door motor and blend door actuator. Is this what I should be looking into? If so how do I access these components and how do I test them once I'm there? All of your help is much appreciated. THANKS!

DennisMik

iTrader: (2)

I had that happen to me on my 97 last winter. The motor for the air mix door died. There are 2 possibilities though. The controls in the dash might not be sending power to the motor and the motor itself.

I would suggest you follow the FSM (the HA section) and determine which part is bad. The control panel in the dash is much easier to change but you would be throwing money away if the motor is the bad part. If you don't have the FSM, you can download one from here:

http://boredmder.com/FSMs/Nissan/Maxima/

The air mix door motor is very hard to get to. It is located right over the ECU and it is even hard to see. You can look from either side footwell but you have to pull the trim panels off that cover the ECU. Here is a photo from the driver's side:



I never did find out the official/proper way to change the motor. If you can get the ECU out of it's mounting, you can probably get the motor out that way. But I couldn't get the ECU out. So I then removed my dash, thinking I could disassemble the big airbox that sits in the center of the dash. I discovered that in order to remove the airbox, you had to drain the cooling system and discharge the a/c because of the evaporator core. I decided I didn't want to do that and ended up cutting the motor's mounting tabs off with a hacksaw blade. I could get to the screws that held the motor on, but they were phillips head and could not get a screwdriver on one or two of them because of the closness of the ECU. After cutting the motor off, I got the screws out with a small vice grips and used hex head screws to install the new motor.

As far as removing the dash goes, it isn't as bad as you might think. Once you've done it, you can do it in a half hour. But the motor is a pita any way you look at it.

Here is a link to removing the dash -

http://forums.maxima.org/4th-generat...dashboard.html

maximagasm

Thanks Dennis for the info and the time you spent to help me out. This definitely gets me going in the right direction

maximagasm

So i located the actuator/motor. Yikes what a mess. I guess what I'm not sure about is how removing the whole dash will really help in terms of accessing the thing. Looks like it will still be blocked by the "air box" (forgive me) on the top and the ECU on the bottom and the only way to get to it will be from the sides..........which is the same situation whether the dash is out or not. I must be missing something.

DennisMik

iTrader: (2)

If you could get the ECU out, I'm pretty sure that you could remove the motor using an offset screwdriver. I could never get my ECU out and I spent lots of time over several days trying.

I removed the dash because I thought I could then remove the "air box" as you have called it. But when I realized that I would have to discharge the a/c to disconnect lines and also drain the cooling system, I decided to do it by brute strength and ignorance, emphasis on the ignorance.

Like I said before, I was able to cut off the mounting tabs for the air mix door motor. I had to saw from the front (or rear, whichever), you can't do it from the sides. I already had the dash removed when I came up with this desperation plan. Could I have done it without removing the dash? I don't really think so. If you remove the radio cluster, the console between the seats and the air ducts for beneath the front seats, I think the chances would still be kind of small. As I recall, I needed to reach in from the side, which would be blocked off by the sides of the dash that go down to the floor. I know that I had to cut tie wraps to move the ECU wire harness out of my way.

As I said in one of my later posts in that dashboard removal thread, I'm sure that with a little more thought, nissan could have made removing that motor absolutely impossible.

Julian88Tex

Wow, thanks for all the info. I'm 90% sure its an issue with my Air Mix Motor. This is so depressing that its so difficult to get out. Is is possible to just force the motor into a cold or hot position? I was able to do that with the Mode Mix Motor.

bigd480

It is possible to rig it to be always cold - the guy that eventually replaced mine did that while I ordered the part - just mess with the actuator arm.

Julian88Tex

bigd480, I did my best on my 99 Maxima... ended up just taking out the heat hose for now. I didn't want to break the arm but honestly it didn't feel like it was budging at all.

DennisMik

iTrader: (2)

[QUOTE=chillywilly;9060450]Hello sir
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I visited your website and it says nothing about automotive air conditioning. What are you qualifications for automotive repair, especially the interior ductwork control systems?

Junebug1701

That's a spammer, I reported the post by clicking on the exclamation point icon.

The Wizard

iTrader: (43)

Adios spammer.

DennisMik

iTrader: (2)

After 11 years on this org, I have been taught something new. Thanks.

NSMO240

iTrader: (5)

bump this up, as I removed the ECU by unbolting the 2 10 mm bolts at the bottom of the ECU bracket and unplugged the 2 small plugs branching of off the harness, pivoted the ECU out of the way and was able to get it out with a small rachet and phillips bit. No dash removal here. now my question is, where can I get the air mix door? Its discontinued from nissan.

EDIT: found part number 27732-2L901 from nissan that is still available, ordered it up and waiting on arrival to see if its a fit or not although on the parts catalog I looked up it said it was, also said it fit both manual and auto air.

DennisMik

iTrader: (2)

The motor is the same for both the auto and manual controls. I hope you get the motor.

Showseeker

Were you able to get it fixed? Any advice you can add?

The Wizard

iTrader: (43)

What are your specific questions?

Several of us, including me, have had to deal with this problem. Once you get the ECU out of the way, and the bracket that holds the ECU in place, the rest is pretty easy.

Order the part and have at it. It's not that hard of a job.

CS_AR

Just to have a replacement on hand for the 98 and 99 model, I just ordered from Naples FL Infiniti @ https://parts.bonitaspringsinfiniti.com/ for $62.98. Shipping was just under $11.

I think this is one of those parts that may not be available forever.