Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Honda Pilot EliteFACTORY OEM SERVICE PROCEDURE
Left Side BSI Radar Unit
LEFT SIDE BSI RADAR UNIT DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC | Description | DTC Type |
|---|---|---|
| B18A1 | Left Side BSI Radar Unit Internal Circuit Error | Internal error |
| B18A5 | Left Side BSI Radar Unit Temperature High | Signal error |
| B18B4 | Left Side BSI Radar Unit Dirty | Signal error |
| B18B8 | Left Side BSI Radar Unit Azimuth Off Alignment | Signal error |
| B18BA | Different Version in the Left and Right Side BSI Radar Unit | Signal error |
| B18C5 | Short to GND in the Left Side BSI Radar Unit Indicator Circuit | Signal error |
| B18C6 | Short to Power in the Left Side BSI Radar Unit Indicator Circuit | Signal error |
| B18C7 | Open in the Left Side BSI Radar Unit Indicator Circuit | Signal error |
| B18DB | Left Side BSI Radar Unit Received The Audio/Navigation Unit Failure Information | Signal error |
| B18EA | Left Side BSI Radar Unit Received PCM (A/T System) Failure Information | Signal error |
| U1280 | Communication Bus Line Error (Bus-Off) | Loss of communication |
| U1281 | Left Side BSI Radar Unit Lost Communication With MICU | Loss of communication |
| U128D | Left Side BSI Radar Unit Lost Communication With Gauge Control Module | Loss of communication |
| U1297 | Left Side BSI Radar Unit Lost Communication With Right Side BSI Radar Unit | Loss of communication |
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.