Stepper Motor Location?

[tim]

How do you get to this puppy? Through the console, the vent or the dreaded microfilter route? I just want to check some of the pins to track down a fault code.

tia,

tim

[shogun]

There are 10 stepper motors in total. Which one do you mean?
On the E32 for the center vents you have to remove the radioo, then you can get to them with small hands.
If you go to my website and then to Johan and Sean's page, click IHKA components, there are all stepper motors shown and their functions, as well as the temp sensors.

[tim]

Thanks Shogun, that's a great site you have, and so is Johan and Sean's. After looking at his pictures of the center console removal, I think I've cured my desire to check these stepper motors.

Tim

[shogun]

Tim,

the easiest to check the function of the stepper motors is to connect the car to the DIS at the dealer. It can be read from the ZKE (central body electronics) diagnosis.
Not possible on older production cars such as my one from 1988 or even 1987.

[tim]

Actually, I got the codes in question from a carsoft diagnostic.

They were
a) 34 layering selector wheel (white pin #21)
b) 61 layering flap motor (pin 23,24,24,26)

I have the three slide knobs for layering in my 540i, and the fresh air mix on the center vent seems to work. It may be that my carsoft is not properly reading my IHKA. But I do occasionally hear that groaning noise behind the dash and figured it was a bad stepper, or a broken flap or flap actuator. I don't get heat in the footwells either so it may be the flap to that one.

-tim

[Bill R.]

early e32 had, I believe the first generation e34 had 6 and then the numbers went down with each new generation ihkr...
Tim, i still think that you don't have an error like i said before. I think that your early version carsoft is misreading your version of the stepper motor software since you have either 2 or 3 stepper motors on your car, instead of the 6 that the model that that software covered had.

This 2nd generation version had 5

This 3rd generation had 3


And I think that your 4th generation version has 2 based on the info that i have.

[John B.]

This brings up a problem I have with my 12/89 production 535i. In order to get good airflow to the defroster I have to shut off the dash & floor functions. Is it possible for the flaps to only partially open? I could live with it but if its easy to fix I might dig in there come summer.

[Bill R.]

control the defrost and the facevents.. they are cable operated as you see here , you might want to pull the glovebox and the side panels on that side of the tunnel and i recall theres a duct you pull too... when they're off you can see the cable operated flaps on that side easily, just work the cables through their range of motion and you may have to disconnect the cable from the flap to set full closed and full open on the flap , then reconnect the cable with it set to full open on the defrost to make sure the flap is opening all the way..
If this doesn't make any sense let me know... here's the view of the right side of the housing from the glovebox side..


Heres the view of the left side by the drivers pedals..


I don't know if you got my PM or not but your Nissan sentra and truck cd manuals are on their way

This brings up a problem I have with my 12/89 production 535i. In order to get good airflow to the defroster I have to shut off the dash & floor functions. Is it possible for the flaps to only partially open? I could live with it but if its easy to fix I might dig in there come summer.

[John B.]

If this doesn't make any sense let me know... here's the view of the right side of the housing from the glovebox side..
I don't know if you got my PM or not but your Nissan sentra and truck cd manuals are on their way

It makes perfect sense, thanks once again Bill. Since I don't have to pull the dash apart I'll try to fix it this weekend. I got your PM on the Cds & put a check in the mail.

[tim]

Bill,

do you happen to have one of those diagrams for my version? Much appreciated.

-tim