OEM Part Numbers

Technical Specifications

Product Description

This is a genuine refurbished OEM Haldex control unit with part number 0AY907554D. It is a critical component of the fourth-generation Haldex all-wheel-drive system, responsible for controlling the rear differential clutch and enabling correct torque transfer to the rear axle when traction is required.

What This Control Module Does

• Controls the rear differential clutch engagement in the AWD system
• Supports proper torque transfer to the rear axle during traction demand
• Communicates with the AWD system and related drivetrain electronics
• Helps restore correct AWD performance when the original module has failed
• Provides an OEM replacement solution for intermittent or complete AWD loss

Vehicle Compatibility

The 0AY907554D is compatible with selected Volkswagen Group vehicles equipped with Gen 4 Haldex AWD. Always verify the exact part number on your existing module before ordering.

Škoda

Volkswagen

Audi

SEAT

Common Symptoms of a Faulty Module

A defective Haldex control unit commonly causes the following issues:

Installation

Installation Steps

• Verify the exact OEM part number on the original control unit
• Disconnect the module and inspect the connector pins and wiring
• Install the replacement module in the original position
• Check the condition of the Haldex pump and N373 valve
• Clear stored fault codes with suitable diagnostic equipment
• Code or adapt the module if required by the vehicle
• Perform a test drive and confirm correct AWD engagement

Why Haldex Control Units Fail

1. Water Ingress & Sealing Failure

Moisture and damaged sealing can affect the control unit housing and internal electronics, leading to corrosion, unstable communication and complete AWD malfunction.

2. Valve or Pump Related Faults

Failure of the Haldex pump or the N373 clutch control valve can overload the system and trigger repeated module-related diagnostic errors.

3. Internal Electronic Failure

EEPROM faults, internal memory errors and circuit-board wear can cause intermittent operation, no communication faults or complete loss of rear differential control.

4. Wiring or Power Supply Problems

Damaged wiring, poor terminal contact or unstable power supply can interrupt module operation and create misleading communication or actuator fault codes.

Quality Assurance & Warranty

12-Month Warranty: This refurbished Haldex control unit has been tested for correct operation and is supplied with a 12-month warranty under normal operating conditions.

Warranty Coverage Includes:

• Internal control unit malfunction
• Communication failures caused by the module itself
• Faults related to internal memory or controller operation

Warranty Exclusions:

• Incorrect installation or incompatible vehicle fitment
• External wiring, pump or valve faults
• Physical damage, water damage after installation or mishandling

Questions or Need Help?

Our technical team is ready to assist with compatibility checks, installation guidance and coding support.

Important Purchase Information

• Please verify this part fits your specific vehicle before placing an order
• Photos are for illustrative purposes only and the supplied unit may differ in appearance
• Worldwide shipping is available
• If your country is not listed at checkout, contact us and the order can be processed manually
• Coding or adaptation may be required after installation and online support is included