Description
Genuine Mercedes-Benz Front SAM Control Module
Genuine OEM Mercedes-Benz Front SAM โ Signal Acquisition and Actuation Module / fuse and relay control box, part number A2129008307.
The Front SAM is an important component of the Mercedes-Benz electrical system and controls or distributes power to numerous vehicle systems through integrated electronics, fuses and relays.
OEM Part Number
A2129008307
Also written as:
- 2129008307
- A 212 900 83 07
- 212 900 83 07
- A212-900-83-07
- 212-900-83-07
Part Type
Front SAM Module / Signal Acquisition Module / Fuse Box / Relay Control Module
Placement
Front / Engine Compartment Electrical System
Vehicle Fitment
Fits select compatible applications including:
Mercedes-Benz E-Class W212
- 2010 Mercedes-Benz E350
- 2011 Mercedes-Benz E350
- 2012 Mercedes-Benz E350
- 2013 Mercedes-Benz E350
- Select Mercedes-Benz E400 applications
- Select Mercedes-Benz E550 applications
- Select Mercedes-Benz E63 AMG applications
Mercedes-Benz E-Class C207 / A207
Compatible with select E-Class Coupe and Convertible applications using the same factory SAM module.
Mercedes-Benz C-Class W204
Compatible with select:
- Mercedes-Benz C250
- Mercedes-Benz C300
- Mercedes-Benz C350
when equipped with the matching A2129008307 Front SAM configuration.
Exact compatibility depends on vehicle production date, electrical equipment, hardware/software revision and original module configuration.
Important Fitment Information
Mercedes-Benz used multiple SAM module revisions that can look physically identical.
Please verify:
- OEM part number
- Fuse layout
- Relay layout
- Electrical connectors
- Hardware revision
- Vehicle production date
- Original module configuration
before ordering.
Exact OEM Number
A2129008307
Exact part-number matching is strongly recommended.
What Is a Mercedes SAM Module?
SAM stands for:
Signal Acquisition and Actuation Module
The SAM receives signals from switches, sensors and other vehicle modules and controls numerous electrical functions through the vehicle CAN network, integrated relays and fuse circuits.
The Front SAM also serves as a major power-distribution and control point for the vehicle’s front electrical systems.
Functions Controlled by the Front SAM
Depending on vehicle equipment, the Front SAM can communicate with or control functions including:
- Exterior lighting
- Headlights
- Parking lights
- Turn signals
- Windshield wipers
- Washer system
- Horn
- Cooling-fan circuits
- Engine-compartment electrical circuits
- Fuse and relay distribution
- CAN-bus communication
- Various sensors and actuators
- Power distribution to multiple vehicle systems
Available functions depend on the vehicle’s original factory configuration.
Common Failure Symptoms
A failing Front SAM module may cause symptoms including:
- Vehicle electrical systems operating intermittently
- Headlights not working correctly
- Turn signals malfunctioning
- Windshield wipers malfunctioning
- Horn not operating
- Blown or repeatedly failing fuses
- Multiple electrical warning messages
- CAN communication faults
- Accessories operating intermittently
- No power to certain circuits
- Multiple unrelated electrical faults
- Diagnostic communication errors
- Vehicle modules reporting missing signals
These symptoms can also be caused by:
- Wiring damage
- Low battery voltage
- Weak battery
- Charging-system problems
- Corrosion
- Water intrusion
- Blown fuses
- Faulty relays
- Other control modules
Proper diagnosis is recommended before replacing the SAM.
Water and Corrosion Inspection
Before installing a replacement SAM module, inspect the vehicle for:
- Water intrusion
- Moisture
- Corroded terminals
- Damaged wiring
- Burned connectors
- Short circuits
- Loose electrical connections
Installing a replacement module without correcting an existing electrical or moisture problem may damage the replacement unit.
Programming / Coding
A replacement Mercedes-Benz SAM module may require vehicle-specific coding or programming after installation.
Configuration may include:
- Vehicle equipment coding
- Variant coding
- CAN-bus configuration
- Module initialization
- Diagnostic fault clearing
- Vehicle-specific electrical configuration
Professional installation with Mercedes-Benz-compatible diagnostic equipment is recommended.
Condition
Used Genuine OEM Mercedes-Benz Part
This is an original previously installed factory electronic component.
Normal cosmetic signs of previous use may include:
- Light scratches
- Surface marks
- Dust
- Label wear
- Installation marks
- Minor cosmetic wear
- Relays not included for display only
Product photographs are representative of the overall style and condition of available inventory.
The unit shipped will be a matching OEM A2129008307 module in comparable used condition.
Fuse and Relay Information
The SAM module incorporates multiple fuses and relays as part of the vehicle electrical system.
Fuse and relay configuration can vary depending on vehicle equipment.
Fuses and relays should be inspected before installation and replaced as necessary according to the vehicle manufacturer’s specifications.
Part Number Verification
Please compare the identification label on your original module with:
A2129008307
or
2129008307
Also verify:
- Electrical connectors
- Fuse layout
- Relay configuration
- Mounting points
- Vehicle chassis
- Production date
Exact-number matching provides the safest method of confirming compatibility.
Installation
Factory-style replacement Front SAM module for compatible Mercedes-Benz applications.
Professional installation is recommended.
Before connecting the module:
- Inspect vehicle wiring
- Inspect connectors
- Check for corrosion
- Check for moisture
- Verify correct fuse ratings
- Verify battery condition
- Verify charging-system voltage
Vehicle coding or diagnostic initialization may be required after installation.
What Is Included
1 ร Genuine Mercedes-Benz Front SAM Module / Fuse Relay Box
Part Number: A2129008307
Only the SAM module and components specifically described with the product are included.
Wiring harnesses, body wiring, additional control modules, mounting hardware and other vehicle components are not included unless specifically stated.
Warranty
Covered by the Ozโs Garage 30-Day Replacement Warranty.
Warranty does not cover damage caused by:
- Incorrect vehicle application
- Improper installation
- Electrical shorts
- Wiring faults
- Water intrusion
- Corrosion
- Low or excessive voltage
- Power surges
- Incorrect fuse installation
- Incorrect programming
- Modification
- Tampering
- Physical damage after delivery
Labor, installation, programming, coding, diagnostic and related vehicle expenses are not covered.
Shipping
The SAM module will be carefully packaged to help protect the:
- Housing
- Internal electronics
- Fuse panel
- Relays
- Electrical connectors
- Mounting points
during transportation.
Usually ships within 1โ2 business days.
๐ Worldwide shipping available.
International buyers are responsible for applicable customs duties, import taxes, brokerage charges and other local fees.
Why Buy From Ozโs Garage?
- Genuine OEM automotive parts
- Hard-to-find factory electronics
- Original Mercedes-Benz components
- 30-Day Replacement Warranty
- Worldwide shipping available
- Usually ships within 1โ2 business days









