Infiniti Q50 Forum banner
41 - 60 of 74 Posts

·
Registered
Joined
·
1,685 Posts
So, being curious like a cat I decided to open up my bad one to see how it works. There is a worm gear on a small electric motor that drives a gear, that drives another gear, that drives another gear, that drives another gear with copper contacts on it. That is a lot of reduction there. I'll assume for very fine grained adjustments.

You'll see that those contacts slide across those black semi-circles on the circuit board. I'm guessing that is some kind of resistive material. Because of the limited resolution, what you can't see is that right in the middle of the range of motion the black stuff is very glossy. Like it is worn. I suspect that contact in that area is marginal causing the motor to drift.

That assumption makes sense as some members here have reported cycling the temp up and down through the range seems to help. I believe that is true but only a temporary fix. That original part number has been superseded twice already. Perhaps the third revision that I now have in my car will outlast me.

View attachment 94343
I think your conclusion makes sense on the failure mode. I suspect typical operation has the assembly operating in a fairly narrow band and over time can wear the feedback strip on the contacts of the board.

I've run into similar failures on linear transducers where I work. To solve that problem, the sensing portion was changed to a non-contact technology.
 
  • Like
Reactions: rpiotro

·
Registered
Joined
·
4,120 Posts
Excellent information! Could it be that the copper contacts aren't touching the black conductive bands in certain spots because they aren't pressing hard enough to make contact?
Perhaps. As the conductive bands wear or the copper contacts.
 

·
Super Moderator
Newport, Oregon
Joined
·
12,790 Posts

·
Registered
Joined
·
4,120 Posts
I think your conclusion makes sense on the failure mode. I suspect typical operation has the assembly operating in a fairly narrow band and over time can wear the feedback strip on the contacts of the board.

I've run into similar failures on linear transducers where I work. To solve that problem, the sensing portion was changed to a non-contact technology.
Optical?
 

·
Registered
Joined
·
4,120 Posts
After driving the car around on a fairly warm day today (80°F) it now seems clear that this was going on for a while. Months? It didn't seem to hold an even temperature like I remembered when it was new. A very slow deterioration is hard to notice. In the last two weeks it suddenly became blatantly obvious.
 

·
Registered
Joined
·
1,685 Posts
Magnetostrictive
 
  • Like
Reactions: rpiotro

·
Registered
Joined
·
4,120 Posts
Magnetostrictive
Fascinating. What WILL they think of next?
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #48 · (Edited)
update:

I have raised my issue with Infiniti region in 2018 and raised it again 2 weeks ago as a follow-up regarding the A/C issue. I received a call from them and I explained that Infiniti should coordinate this problem with the dealer; assisting them with technical analyses.
So after few days the dealer toke my Q50 for one day to retrieve some technical data from the computer system for analyses; to be reviewed by Infiniti region technical stuff.
 

·
Registered
Joined
·
87 Posts
A slight addendum to the blend door actuator replacement process. It may just apply to the 2014 model year - which I have. The right side cover, which is shown to pop off - actually has two screws holding it in. I pried and pulled, and luckily (for me) didn't force things too far. I was able to pop the lower dash off fairly easily once the screw was removed on the left side, under the hood latch. Once the lower dash was "lowered", I was able to see the two screws holding in the right panel, and remove them.

I also found that it was easier to remove the actuator, before removing the small cable connector. Just couldn't get my fingers around it well enough to release the snap.

Oh, and kudos to rpiotro for the notes on the small tube and thermocouple location! I was able to catch the hose before it snaked back into the nether regions behind the dash. Blew off the thermocouple with a slight bit of compressed air.

Took about 40 minutes to pull everything off. Less than 15 to get it all back together.
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #51 ·
update:

The latest suggestion from infiniti is to replace the heater core unit including evaporator, flap controller motors, expansion valve ...etc. ...OMG
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #52 · (Edited)
After my communication and negotiations with the dealer; they agreed to do the replacement for free.
94891
94892
 

·
Registered
Joined
·
4,120 Posts
My communication and negotiations with the dealer; they agreed to do the replacement for free.
OMG! I hope that fixes it and it all goes back together.
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #54 ·
update:

I got my car and used it for a week , I am happy to say the issue is fixed thanks to the collaboration of Infiniti region technicians team ....finally the A/C is cooling normally :)
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #55 ·
update:

After using my Q50 for months I have noticed that the issue is still there, the compressor will stop working.

what else is there to replace?

I am thinking it has to do with the AMPLIFIER CONTROL MODULE AIR CONDITIONER Because when I restart the car it works again normally.
 

·
Super Moderator
Newport, Oregon
Joined
·
12,790 Posts
update:

After using my Q50 for months I have noticed that the issue is still there, the compressor will stop working.

what else is there to replace?

I am thinking it has to do with the AMPLIFIER CONTROL MODULE AIR CONDITIONER Because when I restart the car it works again normally.
I believe you're referring to the A/C Auto Amp which controls the A/C based on signals from various sensors and switches. It might be the problem but without any DTCs to go on, it's hard to say. Did the service department do diagnostics on the A/C Auto Amp? I'd like to think they did since they had the console completely torn out to replace the heater and cooling unit assembly.
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #58 ·
I believe you're referring to the A/C Auto Amp which controls the A/C based on signals from various sensors and switches. It might be the problem but without any DTCs to go on, it's hard to say. Did the service department do diagnostics on the A/C Auto Amp? I'd like to think they did since they had the console completely torn out to replace the heater and cooling unit assembly.
The A/C Auto Amp which controls was replaced too, I have sent this video to Infiniti dealor and now they are rethinking how to solve the issue.
 

·
Super Moderator
Newport, Oregon
Joined
·
12,790 Posts
The A/C Auto Amp which controls was replaced too, I have sent this video to Infiniti dealor and now they are rethinking how to solve the issue.
So what is this Amplifier Control Module Air Conditioner? Never heard of it.
 

·
Registered
Joined
·
137 Posts
Discussion Starter · #60 ·
So what is this Amplifier Control Module Air Conditioner? Never heard of it.
A/C auto amp. controls automatic air conditioning system by inputting
and calculating signals from each sensor and each switch. A/C
auto amp. has self-diagnosis function. Diagnosis of automatic air
conditioning system can be performed quickly.
 
41 - 60 of 74 Posts
Top