Mercedes LED Headlight Control Module - A2129005424

Mercedes-Benz LED Headlight Control Module - A2129005424

Restore proper operation of your Mercedes-Benz LED headlight system with the A2129005424 LED Headlight Control Module.

This module is designed for selected Mercedes-Benz vehicles equipped with factory-fitted Full LED / Intelligent Light System (ILS) headlights. It controls multiple lighting functions, including daytime running lights, indicators, low beam, high beam and other adaptive headlight functions.

Product Details

Part Number: A2129005424
Mercedes-Benz Number: A212 900 54 24
Continental Number: A2C73610906
Hardware Number: A2129014406
Software Number: A2129024008

Main Functions

Depending on the vehicle and headlight configuration, this module may control:

• LED daytime running lights (DRL)
• Low beam
• High beam
• Front indicators / turn signals
• Parking lights
• Intelligent Light System functions
• Adaptive Highbeam Assist
• Headlight electronic control functions

Common Symptoms of a Faulty Module

Replacement may be required if your vehicle displays lighting faults such as:

• Intelligent Light System Inoperative
• Adaptive Highbeam Assist Plus Inoperative
• Adaptive Main Beam System Inoperative
• Left or right dipped beam malfunction
• Daytime running light malfunction
• Front indicator malfunction
• Parking light malfunction
• Intermittent or non-functioning LED headlight
• Headlight control unit communication fault

Common Diagnostic Fault Codes

The module may be associated with fault codes including:

• B1FB201 - Headlamp range adjustment temperature sensor fault
• B285711 - Standing light output malfunction / short circuit to ground
• B286011 - Daytime running light output malfunction / short circuit to ground
• B238601 - Control unit fan malfunction / electrical fault
• B178387 - Right front LED exterior lighting actuation module communication fault

Fault codes may vary depending on the vehicle, headlight and diagnostic equipment used.

Compatible / Cross-Reference Part Numbers

This unit may cross-reference with certain versions of the following modules:

• A2189006604
• A2189009904
• A2129008222
• A2129008324
• A2189000406
• A2129005311
• A2189008108
• A2129003317
• A2189007307

Additional Continental references include:

• A2C74252903
• A2C74252905
• A2C73610904
• A2C73610905
• A2C74767503
• A2C73610902
• A2C75659702

Important: Matching appearance alone does not guarantee compatibility. Always confirm the original module number, hardware/software version and vehicle specification before ordering.

Compatible Mercedes-Benz Models

Suitable for selected vehicles equipped with compatible factory LED headlights, including:

Mercedes-Benz B-Class

• W246 / W242
• Approx. 2014-2018
• B160
• B180
• B200
• B220
• B250

Mercedes-Benz CLS

• C218 Coupe
• X218 Shooting Brake
• Approx. 2011-2018
• CLS220d
• CLS250d
• CLS350
• CLS350d
• CLS400
• CLS500
• CLS63 AMG

Mercedes-Benz E-Class

• W212 Sedan / Saloon Facelift
• S212 Estate / Wagon Facelift
• C207 Coupe Facelift
• A207 Cabriolet / Convertible Facelift
• Approx. 2013-2017
• E200
• E220d
• E250d
• E300
• E350d
• E400
• E550
• E300 BlueTEC Hybrid

Mercedes-Benz GLE / ML

• W166 Facelift
• C292 GLE Coupe
• Approx. 2015-2018
• GLE250d
• GLE300d
• GLE350d
• 4MATIC
• BlueTEC
• AMG Line

Mercedes-Benz GLS

• X166
• Approx. 2015-2018
• GLS350d

Mercedes-Benz Vito / V-Class

• W447
• Approx. 2014-2018
• V220d
• V250d

Compatible Headlight Numbers

May be used with selected headlights carrying numbers such as:

• A1669064503
• A1669064603
• A2129062903
• A2128205639
• A2128205539
• A2078208761
• A2078208861
• A2129063003
• A2079064100

Selected Hella references may include:

• 1EX011066-55
• 1EX011066-56
• 1LX011091-33
• 1LX011091-34
• 1LX011066-84
• 1LX011091-63

Installation & Coding

Professional installation is recommended.

Depending on the vehicle and replacement module version, coding, programming or adaptation may be required after installation.

For best results, compare your original module's complete part number, hardware number and software number before purchase.

Important Compatibility Notice

Vehicle model and year alone are not sufficient to confirm compatibility.

Please verify using:

• Original module part number
• Headlight part number
• VIN
• Hardware/software numbers
• Left or right headlight configuration

This compatibility list is a guide only and is not exhaustive. The module may also fit additional Mercedes-Benz vehicles fitted with the same LED headlight control system.

What's in the box
1 X Headlight Ballast