Ecumaster forum

Hey there from Germany,

I am looking for some examples to control my Haldex system.
If you check the EMU Software, you can see, that there is one option to control PWM#1.
What I know, is that the Haldex System works with an internal Bipolar stepper motor.
I thought, that there could be a chance to control Haldex by PWM signal- Using the Map table- based on Boost. If there is 101 KPA of Pressure, it has to close- so that the AWD will work.

Anyone has ever tried it? I don't want to buy an external Haldex controller....


Thanks guys!

We controlled HALDEX in Golf V just using PWM. We modified the haldex controller to connect directly to the solenoid that controls the oil pressure. Sp then based on PWM table you can control the module.

That sounds great to me!
So I do not have to feed the Stepper with PWM? You just connected it directly to the solenoid or what?
Do you have any refs. how the table could look like?
Thank you

Yes and the higher DC the higher central diff lockup.

I am trying to connect to my EMU the OEM gen2 haldex controller Audi A3.
I was send instruction on how to modify the haldex board so we can connect to the Haldex solenoid.
There is no real info on how to connect to the haldex pump. I should just connect to the haldex solenoid only?
Why on the example I was given on how to set it up I was told to use 2 separate AUX output.One for the PWM and one for boost?
I need help asap. Car is on the lift and I waiting for only this to strap it on the dyno. We have a drag race in 1 week...

the dog wrote:I am trying to connect to my EMU the OEM gen2 haldex controller Audi A3.
I was send instruction on how to modify the haldex board so we can connect to the Haldex solenoid.
There is no real info on how to connect to the haldex pump. I should just connect to the haldex solenoid only?
Why on the example I was given on how to set it up I was told to use 2 separate AUX output.One for the PWM and one for boost?
I need help asap. Car is on the lift and I waiting for only this to strap it on the dyno. We have a drag race in 1 week...

We manage to solve it our self
For Anyone that was a similar question
Originally the haldex pump connects to the 2 pin connector on the haldex controller
So the haldex pump is the 2 wires yellow and black that are left .Yellow is the 12v and black the pwm .

The above sounds very promising! How did it all work out?

Any chance the necessary modifications for the controller will be shared?

I dort want to controll the pump. The pump always stays at the same Dc.
We need to controll the inside stepper. It is bipolar, so stepper 1a,b and 2a,b are needed.
Bitte I dont Know, how I can tell The ecu to controll these 4 Outputs.
I dont think, that The Adminis will help us, because then they would not sell their Controller, I understand that point of view.
I will try to get The haldex running over The weekend. If I will manage to get it running, I will write down, how I did that.

It is not possible to controll haldex steppet motor from emu. You can make own voltage->steper postion controller.

Also how about monitoring oil temperature etc? Are these necessary parameters that a dedicated Haldex controller uses?

Yes,when clutch oil is overheated (>100°C) clutch is disengaging rear axle.
Also max allowed torque depends from oil temp. I think inside oem controller are some tables in function of temp.