Only info I got from the customer was car was driving fine. Loaned car to friend to run to the grocery store and it left her stranded. No info if there was any warning, popping or a sudden snap sound.

@@kevinphillips4469 hello Kevin there could be a few issues but first thing comes to mind is output splines on transmission ( or housing for that splines ) or both in most cases are stripped its between tcase and transmission even the car goes into gear it can’t fully transfer power to transfercase so it turns shafts , it usually happens when people keeps driving with faulty transfer case and it eventually locks up while driving and messes that output splines on transmission

@@kevinphillips4469 one simple test to make sure that vehicle needs both transmission and transfer is try to push the car while shifter in P or try to park car down hill with out parking brake applied if car rolls , connection between transmission and transfer case ( transmission output shaft splines and transfercase input splines ) are stripped , broken chain would not do that specially if your rear driveshaft still turns which eliminates broken chain locked up tcase issue matter fact you wouldn’t have winding noise when you put it in drive anyways

@@kevinphillips4469 and that poor guy borrowed the car has nothing to do with it I can guarantee you owner already had bad tcase for a while now and been driving it like that

Did it fix it?

hello thank you for your comment ,but you are absolutely wrong i have spent so much time understanding the mechanism of this units looked into all the wiring diagrams etc , matter fact as of today i rebuilt over 500 tcase for german cars most europeans have same logic including range rovers , and yes plastic gear and worm gear will turn backward if you apply enough power with a pipe wrench or something that will fit tight inside the spline which i made special tool for it , if it's not turning backward then you have bad plastic gear in it that is sticking

Hi, thank you for your reply, but I have examined an actuator and no way can you turn it backwards.It would risk stripping the gear if I tried hard enough..The helix is too shallow. Plus, although I have not had the experience of stripping an ATC400 there is no sign of the powerful return spring mentioned being shown in any exploded diagram. So your explanation leaves me confused. Bearing in mind I am referring to the ATC400 as fitted to a 2006 BMW X3. Other models may well have a different design. There seem to be lots of contentious things said about the ATC400. My local BMW Indie here in the UK assured me that there was no point even looking at the ATC400 until I had fitted all star rated tyres first. This is clearly rubbish because all the wheels rotate at different speeds evertime you go round any bend in your car, so there is absolutely no need to have tyres all the same size to within a close tolerance. I am almost looking forward to stripping my ATC400 to see whats what in there! I would agree that its never a bad thing to change the oil in the transfer gearbox, and lots of people have stated that it has improved things in the box. I would be the first to admit there are elements of the ATC400 that I do not understand, especially how the control unit electrics work, and the significance of "readjusting the adaption values". Also how the resistor works and what it does. Presumably you can buy different resistors depending on the needs of the transfer box, but they only ever seem to be sold as "resistors" without any reference to different resistance values that might be available. BMW obviously think they have a winning formula with this box as they seem keen to use it on more of their models, despite it having a bit of a chequered reputation amongst customers. Maybe its just not robust enough when faced with clients who like to floor the throttle every time the lights go green. Another interesting question: does the box distribute power by the clutch being made to fully or partially slip all the time in which case you would think its lifetime would be measured in days or weeks, It would, if your main clutch was made to slip all the time.

I have the same car where are the starter relays located? I cannot find them

Located on the passenger side foot well , you need to pull the carpet back Once you get everything out of the way, you’ll see a black box about 2 inches wide and 8” long The relay are behind that little box. Remove that little flap down off that box with a 10 mm

hi we have links in description

hello have you checked the actuator cam where actuator motor sits ? it wasn't loose right you shouldn't be able to turn it by hand ? also another problem , most cheap replacement gears made in china are bad , they won't function properly , i always use expensive made in Europe gears , i tried 20 different plastic gears found most of them faulty

After further diagnostic it has two codes from Restraint A1 and VTG 55C4 both have same code type "No message from DSC" which is anti lock brake module I assume. So I will follow up with those codes. Also have a code 04 set then clear but resets when turning steering wheel more than a have a turn LEW steering angle sensor code 04

Did u get it fixed? If so what was the problem?