[jboyorak]

A few weeks ago I pulled my motor and trans, and after I reinstalled, my awd was not working. I changed my transfer case fluid at throw time as well. I have 4x4! Light, and have the following codes in my transfer case module

52D0 incremental encoder DIR- wire
52D2 incremental encoder IMP- wire
54C9 temperature sensor at actuator.

Connects seem good at the transfercase motor.

If anyone has any insight, it would be much appreciated. I'm almost at the point of throwing a different motor on there, but I'd rather be able to diagnose this properly.

[jboyorak]

In addition, I checked for resistance between the pins on both a new motor the old, both all seem to be identical. I tested the new motor's connector on the bench and the old one at the VGS module under the seat(at the other end of the transfer case motor's harness).

Both resistors (called a class resistor by bmw?) measured about the same. I am not sure if this is actually a temperature sensor.

The only other thing I can think of is maybe their is a short or issue from the transfer case's module to another module?

If anyone has a wiring diagram for the E90 xdrive system, that would be extremely helpful. It's to bad the Bentley manual does not cover this.

I also did try and plug in the new motor to see if the 54c9 code would go away. It did not.

The 54c9 code is present even with the key in the on position. Once cleared it comes back immediately. The others only come on once the car is started.

[Spitzenpradator]

My transfer case seem a bit harsh... My plan was to unplug it completly electric wise... I unplug the small connector but event when I hold the tab on the biggest connector, I simply could not unplus it ...

Any trick ...???

Originally Posted by jboyorak

In addition, I checked for resistance between the pins on both a new motor the old, both all seem to be identical. I tested the new motor's connector on the bench and the old one at the VGS module under the seat(at the other end of the transfer case motor's harness).

Both resistors (called a class resistor by bmw?) measured about the same. I am not sure if this is actually a temperature sensor.

The only other thing I can think of is maybe their is a short or issue from the transfer case's module to another module?

If anyone has a wiring diagram for the E90 xdrive system, that would be extremely helpful. It's to bad the Bentley manual does not cover this.

I also did try and plug in the new motor to see if the 54c9 code would go away. It did not.

The 54c9 code is present even with the key in the on position. Once cleared it comes back immediately. The others only come on once the car is started.