Mercedes-Benz W211 Heated Seat Control Module - Used Original Parts

Diagnosis and Common Symptoms

From the workshop floor, the most frequent complaint for a non-functional heated seat on the W211 platform is not the switch itself, but this control module. The primary indicator is the switch light on the center console: it illuminates for a few seconds and then extinguishes, or it blinks continuously. This behaviour indicates the module has detected a fault in the circuit and has shut down the system as a failsafe.

On a diagnostic scanner (like STAR/Xentry), you will typically find fault codes stored in the upper control panel (UCP) or the module itself. Common codes include:

• 9804: Short circuit in the seat heating cushion.
• 9805: Open circuit in the seat heating cushion.
• 9807 / B1007: Control module N25/5 (or N25/6) has a malfunction.
• Communication faults with the CAN bus.

While a faulty heating element can trigger these codes, the control module itself is a known failure point due to internal component degradation over time, leading to an inability to properly regulate voltage to the heating elements.

Introduction

Restore the essential comfort of your E-Class with a cost-effective, reliable component. This is a Genuine Mercedes-Benz Heated Seat Control Module, carefully extracted and fully validated by our technicians. Each unit is bench-tested to ensure it meets factory operational parameters for power delivery and communication, guaranteeing a functional repair without the expense of a new part.

Product Details

• Brand: Mercedes-Benz
• Model Compatibility: W211 Chassis - E320, E350, E500, E55 AMG, E63 AMG (2003-2009)
• Part Name: Heated Seat Control Module (Designation N25/5 or N25/6)
• Condition: Genuine Used (Tested Working)
• Notes: This is a direct plug-and-play unit. It is highly recommended to measure the resistance of your seat's heating element before installing this module. A shorted heating element is the primary cause of module failure and will damage the replacement part.