hey mike would you need the car or just the diff and ecu
All I need is the unit on the diff with the motor/actuator and temp sender. I have read a couple of the VW self study documents about the Haldex diff, one shows the actuator as a motor, another shows it as a solenoid, so I need to see one to finally work out once and for all what type it is.
I have a couple of guys offering the bits to help me and then to trial the controller. I should be able to get started on it quite soon.
i have a pdf i think marcel or wilco sent me with all the different versions of haldex controllers they do post your email i can forward it on
makes for good reading etc
Hi guys, following a rather long time away from things, I want to get back and pick up where I left off with the development of a standalone Haldex controller.
So back were I was before, I need to obtain a Haldex controller to work on. Does anyone have one kicking about that I could have to develop the circuit and software?
Any help would be appreciated,
Nice to have you back! 
hi i have one would you need the diff as well ?
and where abouts are you cheers
Hi, all I need is the control module that bolts on the side of the diff. I need to do some tests and investigation, would this be a loan or a gimme?,because this may limit what I can do, I’m not sure how destructive my testing will be!!
BTW I live in Dover Kent!!
Hi Guys, just a quick update on my efforts to develop a haldex standalone controller. I have the main control software written but I still need an original controller so I can finish the power control subroutines.
Can I get opinions on how the transfer ratio is selected?
my thoughts are either a rotary control….like a volume control or 2 buttons….up/down?
I can do either but your ideas?
sorry for being a bit of a donkey, I can’t get my picture to upload..any ideas?
do it as a rotary (potentiometer)
i will be interested in one of these when completed
Hi Thanks for that Joe,
I guess at the end of the day I can do either, the switches are easier to implement in the software but I guess the rotary is the easier from a user point of view. I’m going to start with the switches first and go to the rotary when I get it all working.
Now here’s the thing…when I started all this I had a 20vt Rallye and was thinking of going to haldex as I broke a couple of gearboxes.
I’ve since moved on and I no longer have the Rallye and no longer have the incentive or need to do this for myself.
The problem I now have is I can’t justfy buying a rear diff or even the controller when I will never need them, so I need a partner (or not) who is prepared to supply a controller to me to look at/test/work on.
The upside of this is that they will get to trial my controller, have the opportunity to have an input on the production side of things and of course get one for cost price.
And the down side? well it might not ever happen!! I’m not a profesional programmer, I’m doing this for the fun, the challange, what ever you want to call it, I might damage the controller when I test it, work on it, or just bugger it up. and finally I might not have the skills to complete the project!!!. so no guarantee’s …..anyone interested in taking a chance? or be in a position to help out?
I will leave things a couple of weeks, If I have no positive response then I will give it up once and for all.
i do have a haldex controller lying about but it is in pieces as i was going to have a go at making my own controller myself i dont think iv’e got enough knowhow to do it if you want i can try and put it back together and bung it in the post or do you just need the bi-polar stepper motor and temp sender?
how exactly were you planning to control?
hi Joes, If you could try to put it back together and send it to me that would be great! I can’t make too much of a plan until I see the pcb and the layout. My guess is I will be removing the pcb and controlling the motor and temp sensor direct from the main dashboard control.
the plan….lcd dashboard display and rotary control. display will initially show a system/wiring check, then show diff oil temp, and front/rear transmission ratio from f/r 100:0 to 50:50 in 5% steps.
the diff will fully unlock if, system fail (wiring short or open circuit) diff oil temp too high, handbrake on, footbrake on.
I will have to do some further checks as I believe the main diff oil pump has to be controlled too.
Thats the basis of the controller I have planned at the moment, I’m happy to look at other options or ideas!
I might be able to adapt it more once I have got one running ok.
ie connected to the ABS etc… but one step at a time….
Are you interested in assisting me with testing the unit? how close are you to being ready for a controller?
Sounds very promising…..great!!
il try and bung it back together in the next couple of days, i think you will have to do away with the pcb and run them off your own controller.
plan is sounding good i was thinking also a 3 position switch so one position would be an off the second position being a manual on to whatever the pot is set at and three being an automatic running off a pressure simular to the controller shown on the first page. but as you said maybe not straight away though.
how far away am i from being ready well im building a mk1 golf r32 also built the haldex in the back hense all of this lol. still got a bit of work to do yet but 90% of the running gear is in inc engine and ecu still got to map it yet though so shouldnt be massively long but not for a little while yet.