[alyqc]

hi guys,

First of all, sorry for my english, not my primary language .

Long short story, i looked around multiple of post about transfercase light(4x4!) light and fault but found nothing.

I have an E91 328xi 2012 manual and everytime i start the car, light 4x4! comes instantly. I have ISTA d ans did a scan- 2 main fault came back everytime :

-53FD VTG supply terminal 30g
-5F3A DSC transfer case internal.

First thing, i checked the 2 fuses F26 and F40 , both are good

Second, i know about the FAMOUS trasnfer actuator worm gear , so lift the car and remove actuator, i opened this one and found nothing worn/broke inside , all good. It can be electrical fault , so I check the current consumption on ISTA D and saw 0A for the actuator... i orded new actuator and will wait for shipping .

BUT i decided to checked voltage value inside the VTG :

Voltage At VTG(terminal 30) = 12v
Voltage at VTG(termnal 30g)= 7,85 v

Terminal 30G seems to be too low...

My wife have the same car , so did the same ecu fonction and on her car (no fault and no light) the Voltage at VTG termnial 30g is around 11.85-12V

Can it be the VTG unit who is dead and need to be replace , or the VTG actuator can cause this problem ??

thanks for the help

[gbalthrop]

Originally Posted by alyqc

... E91 328xi 2012 manual and everytime i start the car, light 4x4! comes instantly. I have ISTA d ans did a scan- 2 main fault came back everytime :

-53FD VTG supply terminal 30g
-5F3A DSC transfer case internal.

First thing, i checked the 2 fuses F26 and F40 , both are good...BUT i decided to checked voltage value inside the VTG :

Voltage At VTG(terminal 30) = 12v
Voltage at VTG(termnal 30g)= 7,85 v

Terminal 30G seems to be too low... [BINGO]

As you probably know, Terminal 30G means 30"Switched" (Geschaltet in German) Battery power where Direct/ Unswitched battery power is Terminal 30. So F26 (5A) should have near-Zero V with Ignition OFF, and ~ 12.0V with ignition ON. Likewise, with Ignition ON, that 12.0+ voltage should be measured at Pin #8 of Connector X10594 at the VTG Module. Here are the VTG module wiring diagram, as well as Installation Location of X10594 and its Connector View:
https://www.newtis.info/tisv2/a/en/e...l-unit/jW8PwVH
https://www.newtis.info/tisv2/a/en/e...i-tou/2c7wBQeU
https://www.newtis.info/tisv2/a/en/e...i-tou/CT71PcUn

If you've had water in passenger footwell, corroded pins or even blown fuse #26 (check electrically) are quite possible. BTW, INPA > VGSG/VTG > F5 Status > F3 Terminal Voltage will show the actual voltage as received by the VTG Module at Connector X10594. I assume ISTA shows the same thing. The 53FD Code is telling you what your voltmeter is telling you. Fuse F26 Voltage output (Terminal 30G) TOO LOW, at least as received by VTG. Assuming other Terminal 30G power supply devices are operating properly, that means an issue between F26 & VTG X10594/8.

Votre anglais est meilleur que la plupart des autres.
(Je ne parle pas bien le français)

George

[alyqc]

thanks for the answer!

yes I did mesure my voltage at X10594 pin8, ignition on i have around 12v .

fuse 26 is good and VTG no corrored pins, i open the control unit to see if water can damage and no signs of corrosion...

i also did these test :

ohm test , disconnect VTG connectors, pull F26 and DSC unit (F26 is same fuse for this unit) and did short to ground test= no fault

ohm test of the rt/gr wire from F26, and result was around 0.5 - 1 ohm

this is why i probably think its more the unit its self...wire side looks good

[gbalthrop]

Originally Posted by alyqc

...
yes I did mesure my voltage at X10594 pin8, ignition on i have around 12v...

I'm NOT understanding several things:

1) In your FIRST Post, you stated: "i decided to checked voltage value inside the VTG : Voltage At VTG(terminal 30) = 12v; Voltage at VTG (termnal 30g)= 7,85 v"

2) WHERE did you measure "Voltage at VTG (terminal 30g) - 7.85V"? You said "inside the VTG". Do you mean you have 12V at X10594/8, but LESS Voltage at some point INSIDE an opened A70006 Module?

3) I have never inspected the inside of the VTG Module, A70006 in the Schematic, but what MIGHT be more helpful is to disconnect the 2nd Connector attached to A70006, which is X80003 and appears to be 8-pin connector identical to X10594. Then see if you can clear the "53FD" Fault Code and see if it returns with Ignition on, and/or see if there is a Voltage change at X10594/8 between X80003 connected/NOT connected. That may offer some clues as to whether there is a short in the Actuator Motor, M8533, or its wiring/connector.

You seem to understand that Schematic better than I do. I'm just starting to think of different things that might cause the 53FD Code to be set. IF the 30G F26 is OK, and you have 12V+ at X10594/8 with ignition ON, then (1) where is INPA Reading "Terminal 30G" voltage, and (2) WHERE is that voltage being read for purposes of Fault 53FD??

I have MORE Questions than Answers, so probably NOT helpful.

George

[alyqc]

Questions is always helpfull to find the right answer at the end! I like it


Maybe i was not very clear for my test .

1)Reading of 7,85v at terminal 30G was with INPA connected to the car. So it’s what’s VTG unit see .

2) i decided to confirm the inpa values by mesured the voltage at x10595/8 ... result 12V clear . I didnt mesur any voltage inside the VTG i only opened up to see if corossion was there

3) good idea! I will disconnect the x80003 and do a test with inpa to see if 12v is now on terminal 30g ... if yes actuator motor is short inside or wiring from actuator have problems

If fault and 7,85v is still on 30G see by inpa, i will removed pin 8 from x10594 and add new wire with same terminal and give a 12v to pin 8 of VTG . Like this , i eliminate the wire to confirm if the VTG is dead

If its VTG the problem, i saw a lot of them on EBAY, can i buy one and do the programs to works on my car? Do you have already done this before? (I never used Winkfp but already did coding stuff with NCSexpert)


Thanks George for your help

[alyqc]

*** i bought the car 1 week ago from a car dealer , the problem was there before i bought it... so i dont know anything about water damage... it can be a possibility

[gbalthrop]

Originally Posted by alyqc

...
1)Reading of 7,85v at terminal 30G was with INPA connected to the car. So it’s what’s VTG unit see .

2) i decided to confirm the inpa values by mesured the voltage at x10595/8 ... result 12V clear . I didnt mesur any voltage inside the VTG i only opened up to see if corossion was there

3) I will disconnect the x80003 and do a test with inpa to see if 12v is now on terminal 30g ... if yes actuator motor is short inside or wiring from actuator have problems

If fault and 7,85v is still on 30G see by inpa, i will removed pin 8 from x10594 and add new wire with same terminal and give a 12v to pin 8 of VTG . Like this , i eliminate the wire to confirm if the VTG is dead

If its VTG the problem, i saw a lot of them on EBAY, can i buy one and do the programs to works on my car? Do you have already done this before? (I never used Winkfp but already did coding stuff with NCSexpert)

You and I both appear to like a GOOD PUZZLE!

Simply looking at the wiring diagram and the two codes, along with the INPA readout of 7.85V for Terminal 30G, which is a voltage reading INSIDE the A70006 Module, my SWAG is that there is an issue IN the Module, or at least where Pin #8 attaches TO the PCB. I would try using INPA to view 30G Voltage AFTER removing Connector X80003. If 30G is still < 12V I would FIRST pull F26 and see if either 30G voltage goes to "0", or communication with the Module is lost. That would confirm we are correctly interpreting the INPA Screen.

My interpretation of the TIS wiring diagram is that Fuse F40 (30A) powers the Actuator Motor at the Transfer Case, and Fuse F26 (5A) powers the Control Module A70006, and PERHAPS the Electronics IN/AT the Actuator (M8533). ISTA provides additonal functional identification of the various wires that go from X80003 to the Actuator Electronics, using the "Overview" button at the "VTG Transmission Control" wiring diagram. I have NO IDEA what the "Classification Resistor" function is (R8554), but it's shown beneath the Actuator Motor, under the car.

I would then disconnect the A70006 Module and examine as described below, keeping in mind I have NEVER even looked at the Outside of that Module on mine.

I'm NOT an Electronics Expert, but I would take a half-hour or so to remove the Module and examine as follows. Use a bright light & ~ 3x Magnification. Identify Pin #8 where Connector X10594 connects. Open the Module case, and follow that pin to the Resistor and/or Transistor that the wiring diagram suggests it is connected to. You could use a DMM to measure resistance between Pin #8 and the solder joint of the FIRST component it connects to on the PCB.

I have NO IDEA what it looks like, but I would expect solder joints where pin attaches to board and board links to Resistor and Transistor. I would look for ANY cracks in solder joints, probably NOT obvious without magnification & bright light. I would also look for any sign of heat-damaged resistor or Transistor.

If you see something suspicious in that area, perhaps an Electronics Repair Shop (if there IS any such thing anymore) can replace failed component on board &/or tidy-up the solder. I have repaired cracked solder joints on a PCB (Printed Circuit Board) myself some years ago with a solder sucker and small soldering iron with silver solder, even though I don't understand the electronics on the board. It is possible that the solder joint where the pin attaches to the PCB is cracked, acting as a resistor, and THAT is reducing Voltage measured internally.

Please let us know what you find,
George

[alyqc]

ahah yes i like the way you think !


Tonight, i did some test as you mentioned.

-Pull connector X80003 out of VTG A70006, connected inpa , and same thing reading is 7,xx V

-Pull F26, no more communication with A70006

-I did Back probing with needle on x10595/8, ignition on and reading in voltmeter confirm 12v at x10595/8

-To be sure and eliminate wire resistance with rd/gr from F26 to x10595/8 , i jump a 12v from the 5a fuse and attached to x10595/8 with backprobing needle and same result = inpa reading 7,xx V ...

I opened the VTG unit and saw nothing for the moment, inside looked clean. I will look at it tomorrow and do some mesure with ohm test...I will start to look for new unit in case if nothing can be done.


Do you have any info how to program an used unit with inpa/Ncsexpert/winkfp ?

[alyqc]

Here’s some news...


I bought a used VTG unit on ebay with the same Partnumber from an E60 chassis.

Plug it today and run ISTA D, check for voltage on terminal 30g of VTG and FINALLY i had 12v+!

Old VTG had water damage but no visual sign..


Now, i did some coding,

1) i had to transfer clutch wear values from old unit to new= done
2) classification resistor reset = done
3) control unit reset = crash everytime because fault is present inside VTG

Reading fault and i have 52D1 now but when i read my value of unit i saw calibration is not done. I tried with ISTA but cant do it always have communication error...

I think i will need NCS expert for the finalisation...


Any input will be great! Thanks

[gbalthrop]

Originally Posted by alyqc

...
3) control unit reset = crash everytime because fault is present inside VTG
Reading fault and i have 52D1 now

I don't have any personal experience with the Transfer Case Servo Motor, but as I read the BMW Fault Code Lookup Definition of that code, there is an Electronic Component (Incremental Transducer) in the Actuator Motor which is faulty:
52D1 | VTG: Incremental transducer in servomotor, supply | vgsg90
https://www.newtis.info/tisv2/a/en/e...l-unit/jW8PwVH

I don't know if the Transducer converts torque to a voltage signal or what. Hopefully, you can find someone locally who is sufficiently familiar with that Definition, device & Fault Code to be able to tell you if you should replace the Actuator Motor, or if your existing Actuator Unit can be repaired.

Please let us know what you find,
George

[alyqc]

Hi george,

Here’s some update...

I received my new Transfercase actuator and replace it tonight. Did calibration for classification resistor and when came the time for actutor calibration, same problems as before, fault came in.

I have the same 52D1 error

I think the problem will be around wiring... i know i had a 12v to the actuator motor(pin 1-8) but the other pins i had low 7v 3V 5V... i dont know whats the specs voltage for these pins

What do you think?
Thanks