OEM Part Numbers & Cross-References

Technical Specifications

Product Description

This is a used OEM Haldex control unit with part number 1K0907554L, intended for second-generation Haldex AWD systems used in Volkswagen Group vehicles. The module controls rear differential engagement, supports torque transfer to the rear axle and communicates with the vehicle’s drivetrain and stability systems.

What This Control Unit Does

• Controls the Haldex coupling for rear-wheel engagement when traction is needed
• Helps restore proper AWD / 4x4 operation in VAG applications
• Communicates with ABS / ESP and related drivetrain systems
• Stores and reports diagnostic trouble codes when faults occur
• Supports stable rear axle engagement in low-grip conditions

Vehicle Compatibility

This Haldex controller is intended for VAG AWD vehicles using the matching Gen 2 rear differential control unit. Always verify the exact number on your original module before purchase.

Volkswagen Group

Common Diagnostic Fault Codes & Symptoms

Problems with the Haldex control unit can trigger communication faults, pump or valve faults, and dashboard warning lights. Common fault codes and symptoms include:

Installation & Recommended Service

Installation Notes

• Disconnect the battery and safely access the Haldex module on the rear differential
• Remove the old controller and inspect the connector pins and housing for corrosion or moisture
• Install the replacement ECU carefully and reconnect all plugs securely
• Clear fault codes and confirm AWD module communication with a suitable diagnostic tool
• Carry out coding or adaptation if required by the vehicle after installation

Recommended While Replacing the Unit

• Replace the Haldex control valve N373 when replacing the control unit
• Inspect the Haldex clutch pump if related faults are stored
• Check the wiring, connectors and surrounding module area
• Verify AWD operation after installation and road test

Why Haldex Control Units Fail

1. Moisture Ingress & Corrosion

Water or condensation inside the module housing can damage the electronics and interrupt communication with the AWD system.

2. Pump or Valve Faults

Failures in the Haldex clutch pump or N373 valve can overload the ECU and trigger repeated drivetrain faults or rear axle disengagement.

3. Internal Electronic Failure

Age, vibration and temperature cycling can lead to internal circuit failure, memory errors and unstable AWD operation.

4. Wiring or Connector Problems

Corroded plugs, damaged wiring or weak power supply can create no-communication errors and unreliable AWD function.

Warranty & Support

Warranty of Functionality: This used Haldex control unit is supplied with functionality warranty and online support in case the module needs coding or installation guidance.

Support Includes:

• Compatibility guidance before purchase
• Basic installation and coding advice
• Help with identifying common diagnostic issues

Questions or Need Help?

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

Important Purchase Information

• Please verify this module fits your specific vehicle before placing an order
• Worldwide shipping is available – if your country is not shown at checkout, contact directly for manual processing
• Replacing the Haldex valve N373 is recommended when fitting a replacement ECU
• Online support is included if the module needs coding assistance