2020 RDX Blind Spot Information (BSI) System Malfunction

ClearTheCode admin answer:

A 'Blind Spot Information System Malfunction' on your 2020 Acura RDX Advance, especially after heavy rain, points towards a few common electrical causes. The BSI system relies on radar sensors typically located inside the rear bumper corners.

1. Potential Causes:

   • Water Intrusion/Corrosion: Heavy rain can sometimes lead to water getting into sensor connectors or even the sensor module itself, causing short circuits or corrosion. This is a common issue for exterior-mounted electronics.
   • Blocked Sensors: Although you cleaned them, sometimes persistent moisture, mud, or even a minor impact can obscure or misalign the radar sensors.
   • Wiring Damage: The wiring harness leading to the BSI sensors can be susceptible to damage from road debris or even rodents, especially in the rear bumper area.
   • Faulty Sensor/Module: Less commonly, the sensor itself or the BSI control module could be failing.

2. Troubleshooting Steps:

   • Visual Inspection: Carefully inspect the rear bumper area for any visible damage or signs of moisture around where the sensors are located. Look for frayed wires or corroded connectors if you can access them.
   • Check for OBD-II Codes: A BSI malfunction should trigger specific diagnostic trouble codes (DTCs) in the vehicle's computer system. These are typically manufacturer-specific codes (e.g., B-codes or U-codes) that a standard OBD-II scanner might not read, but a more advanced scanner or dealership tool will. Common codes might indicate communication errors (U-codes) or sensor performance issues (B-codes).
   • Reset System: Sometimes, a simple battery disconnect for 15-20 minutes can reset the system, though this is a temporary fix if an underlying issue exists.

3. When to See a Shop:

   • Given that you've already tried basic cleaning, and the issue persists, it's highly recommended to take your RDX to an Acura dealership or a specialist shop.
   • They have the necessary diagnostic equipment to read the specific BSI system codes, test the individual sensors, and check the wiring integrity. If a sensor or module needs replacement, professional recalibration of the BSI system is often required, which can only be done with specialized tools.