RMC2_a355 airbag control unit fault

What does error code RMC2_a355 mean?

Error code RMC2_a355 indicates a specific fault in the left front impact sensor or its control circuit. The airbag control module (RCM) has detected an issue in this sensor’s signal chain. This could point to a defective sensor, a broken wire, or an internal hardware failure within the control module itself.

Technically speaking, the RCM continuously monitors the readings from the impact sensor, which provides critical deceleration data during a crash. If the signals received from the sensor are implausible, fall outside acceptable tolerances, or are completely absent, error code RMC2_a355 is triggered. In response, the system enters a safety mode and deactivates certain components of the restraint system to prevent unintended deployments.

The root cause is typically found at the hardware level—whether it’s the sensor itself, the wiring harness, or the input circuitry on the control module’s printed circuit board. A purely software-related issue is uncommon for this type of fault.

What symptoms indicate RMC2_a355?

The primary and unmistakable symptom of error code RMC2_a355 is the permanently illuminated airbag warning light in the vehicle’s dashboard. Additionally, a specific diagnostic message may appear on the central display, signaling a malfunction in the airbag system. This potentially compromises occupant safety.

The airbag warning light fails to extinguish after starting the vehicle, indicating that the system has detected an active fault and is no longer fully operational. Consequently, proper deployment of the airbags in the event of a crash cannot be guaranteed.

In rare cases, the control module may also refuse communication with external diagnostic tools, though this usually signals more severe internal defects.

What causes RMC2_a355?

The most common cause of error code RMC2_a355 is a hardware defect. This can directly affect the impact sensor, disrupt the electrical connection to the control module, or result from a fault within the control module’s circuit board itself. Often, additional error codes for other sensors appear concurrently.

First and foremost is a defect in the left front impact sensor itself, which may arise due to aging, moisture ingress, or mechanical damage.

Another frequent culprit is wiring issues: a broken cable, corroded connector contacts, or a short circuit in the sensor’s power line can interrupt communication with the control module.

Lastly, the airbag control module (RCM) itself might suffer an internal fault, often involving the component on the circuit board responsible for processing the sensor signal. In such cases, related errors like RMC2_a356 (right front sensor), RMC2_a357 (left rear sensor), or RMC2_a358 (right rear sensor) frequently occur as well.

Which models exhibit RMC2_a355?

Error code RMC2_a355 specifically affects Tesla vehicles, particularly the high-volume Model 3, Model X, and Model Y series across various trim levels. At Airbag24, we professionally repair control modules for these models.

Specifically, Airbag24 offers repairs for the following models and variants:

Tesla: Model 3 Standard Range, Model 3 Standard Range Plus, Model 3 Long Range, Model 3 Long Range AWD, Model 3 Long Range RWD, Model X 90D, Model X Plaid.

How is RMC2_a355 professionally repaired?

Professional repair of error code RMC2_a355 focuses on restoring the removed airbag control module. Upon submission to Airbag24, the unit undergoes meticulous electronic analysis. Defective components on the circuit board are identified and replaced, followed by a software reset and a comprehensive functional test.

The process at Airbag24 follows established procedures. After receiving the control module, an initial inspection verifies the reported fault, including a detailed measurement-based examination of the sensor-related circuits on the board.

This is then followed by actual component-level repair. Our technicians resolder faulty parts such as resistors, capacitors, or driver ICs, or replace them entirely. Cold solder joints are also corrected.

Following hardware restoration, the fault memory is cleared, and the unit undergoes a final simulation test to ensure all systems function correctly. The repaired control module is then returned for direct reinstallation and is immediately ready for use. We provide 2 years' statutory liability for defects on all repairs.

Is Repair Worth It for RMC2_a355?

Yes, repair is the most economically and technically sensible solution. Compared to a new part, which can cost between 800 and 1,500 euros depending on the model, repair offers savings of 50–70%. The repaired control unit is a plug-and-play solution and requires no reprogramming in the vehicle.

While repair costs typically range from 150 to 300 euros, you avoid the high purchase price of a new component. Additionally, repair is a sustainable alternative, as valuable electronic components are preserved.

Another advantage is that the original control unit remains in the vehicle, keeping the vehicle’s configuration unchanged. This prevents compatibility issues that can arise with new or used replacement parts. 2 years' statutory liability for defects on the work performed provides added peace of mind.