@OtisDette er noe annet, noa ala kalibrering av x-drive clutcher.
For å starte pumpa for å lufte er det nok med en liten kjøring med hjulene i været på bukken. Etterpå så går det ofte på en liten desiliter til med olje.
https://www.haldexrepairs.co.uk/generation-5-haldex-fault-finding-repair-guide/
Pump Learn Function
It is common for owners to have a new pump fitted by a garage or main dealer and still the problem persists. When fitting a pump, or even just after a clean out and service it is essential to carry out the “pump learn” function in the “basic settings” of the Haldex control unit, VCDS/VAGCOM can do this and so can the main dealer ODIS system. Customers are often told there is “no adaption” or programming required to fit a new pump, this is incorrect!
The control unit learns how much power is required to run the pump until the pressure hits a certain threshold, it does this by monitoring how much current is consumed by the pump, when the pump is blocked, or faulty, the control unit learns/adapts some very low values which means when the Haldex controller tried to engage the pump, it does not supply enough power to make it engage. By carrying out the learn function when fitting a new pump, it will learn the correct power values and thus engage the system correctly.
Literally multiple times a week we get customers calling who have had new pumps fitted, often by main VW, Audi, or Skoda dealership, yet the system still does not work and they will not perform the pump learn process. Instead they then quote the customers on a brand new ECU/Haldex Controller, or they quote them on a complete new coupling/rear diff, plus labour. There is no documentation we know of in the “VAG Self Study Guides” / VAG workshop manuals that have any reference to the Pump Calibration / Learn function.
Very very rarely, the pressure relief blow off valve will stick open, this will cause the coupling to not engage 4wd as there is no oil pressure there to clamp the clutch plates together. We have brand new valves in stock, they are easy to replace and not very expensive.
Essentially what the learn function does, and you can listen to the pump run while it does it; the function ramps up the power to the pump slowly until the pressure hits the 44 bar blow off valve where is senses the drop in current. It does it a few times so the pump knows how much current and voltage it takes to achieve 44 bar. It then saves this value in the calibration values, and after a short drive it then calculates/estimates the 1 bar and 15 bar from the last measured 44 bar value.
AFTER THE LEARN HAS “COMPLETED SUCCESS”, THE VALUES USUALLY SAY “0” UNTIL THE VEHICLE IS TAKEN FOR A SHORT DRIVE, THIS IS DUE TO IT ESTIMATING THE 1 & 15 BAR VALUES FROM USE.
MAKE SURE YOU HAVE THE ENGINE RUNNING TO SUCCESSFULLY CARRY OUT THE PUMP LEARN FUNCTION!