[BMW60]

2008 bmw 328xi


Hey everybody (is there a proper way for starting a thread…?) my car has the dreaded trifecta of warning lights (brake, abs, DSC) along with a 4x4 warning, and the AWD system is offline. See picture. (ignore the other lights… I’ll get there eventually.)

A little background, this error has been present for a while. It’s only now that I’m doing something about it. I took it to AutoZone to have the fault codes read, and got this:

5F3A - Clutch Gearbox-ECU: VG-Malfunction - Clutch Is Open - Rear Wheel Drive!

I’m not sure what’s wrong… but here’s some notes:

I just replaced the mechanical part of the transfer case (not the actuator motor), it needed replaced even if it wasn’t causing these problems. Not sure if it leaked fluid or what, but there was metal shavings and broken gears inside the old TC.

When I replaced it, I changed the TC fluid.

I also tested the motor outside of the TC by starting the car and watching the startup procedure (when the car started, the actuator motor rotated a little bit, like a startup calibration.)

The inside of the TC motor looked fine, the worm gear wasn’t stripped.

I checked what I think are the TC fuses, and they aren’t blown.

I know I have a deformed wheel speed sensor ring, and got multiple codes for bad wheel speed sensors from autozone. I’m assuming this wouldn’t cause the AWD to malfunction…

One possibility I have on my mind is the control module for the TC, the one under the passenger carpet. Does anyone have any other ideas or suggestions? The car drives fine other than being RWD without traction control.

[drawz]

Pretty sure wheel speed sensor problems can disable AWD. That's how it knows a wheel is slipping. You should post all the codes that were read. I'm surprised Autozone was able to read BMW specific codes, but good to know that's an option.

[BMW60]

Good to know bad wheel speed sensors could cause that, I’ll work on getting those replaced and hopefully that fixes the problem 🤞

Here’s the full report, one wheel speed sensor has a “noise monitor” error. I pulled the wheel speed sensor off and noticed that the ABS ring is slightly deformed. I’ll add a picture of that.

Does anyone know the part number or where I could find a new ABS ring? I’ve checked on FCP Euro and RockAuto and can’t find one that says it fits the AWD model. Here’s the closest I found. If the hubs are the same I’ll just go for it.


https://www.fcpeuro.com/products/bmw...vD_BwE#fitment

[drawz]

All the wheel speed sensors throwing a code at the same time can’t just be a coincidence. There must be a common point of failure. Did you clear all codes and see what comes back?

[BMW60]

I borrowed a scanner from a friend for that reason, it lets me clear engine codes but not ABS codes. I might just not know how to use it, but it only shows me engine codes.