What is Volkswagen Haldex?
Haldex is the standard intelligent all-wheel drive system found on a variety of Volkswagen Automotive Group models, but is most associated with current-generation cars using VW’s MQB platform.
How do I know if Haldex is working?
Disengage the clutch and run up the engine to 3000 – 4000 rpm. Let the car roll to full stop. * If the coupling is working the car will stop in about half the distance in case 2 compared with case 1. * If there is no difference in the two cases there is a malfunction of the coupling.
What is Audi Haldex system?
– What most people refer to as the Haldex is a coupling system attached to a traditional type rear differential that allows the rear drive to be brought in and out as it is needed. – The Haldex pump provides oil pressure, which actuates the clutches to bring in rear drive as and when the ECU requests it.
How does Gen 4 Haldex work?
When the ABS/TC/ESP ECU detects the front wheels are rotating faster than the rear wheels by the ABS wheel speed sensors, the Haldex ECU is told to engage the Haldex Clutch pack, thus engaging the 4wd system. It then holds the 4wd system engaged until the Torque request from the Engine ECU drops.
What does a Haldex pump do?
The Haldex pump provides oil pressure, which helps the clutches activate rear wheel drive when required. Without this, you could get into trouble off-road. If the filter or oil strainer clogs up, the oil could become dirty and ineffective.
What is the Haldex ECU?
The Haldex ECU is programmed and the PCB customised to specification to VW/Audi group.
Can a Haldex ECU give a pump fault code?
This can manifest itself in sneaky ways on Generation 4 Haldex vehicles. It can give any of the fault codes above, and even pump fault codes. As it depends which area of the circuit board is either corroded and/or burnt out. The most simple way to prove the ECU is at fault is to open the ECU up.
How does the Haldex system work?
It is very fast at responding, it typically engages the 4wd system after around 90 degrees of front wheel slippage. It then holds the 4wd system engaged until the Torque request from the Engine ECU drops. The system disengages if the foot brake or the handbrake is engaged. The Haldex system is not manufactured or designed by VW/Audi group.
What is Generation 4 Haldex system?
A wet clutch pack like a motorcycle clutch, which is clamped together with a piston type actuator built into the assembly VW Audi reduced the specification of the Generation 4 Haldex System by ditching the pressure sensor which Generation 2 systems had, this detected how much oil pressure the pump and filter system was delivering.