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
Heating/Air Conditioning DTCS
HEATING/AIR CONDITIONING DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC | Description | DTC Type |
|---|---|---|
| B1220 | A short in the recirculation control motor circuit | Signal error |
| B1221 | An open in the rear mode control motor circuit | Signal error |
| B1222 | A short in the rear mode control motor circuit | Signal error |
| B1223 | A problem in the rear blower motor circuit | Signal error |
| B1231 | An open in the evaporator temperature sensor circuit (front) | Signal error |
| B1232 | A short in the evaporator temperature sensor circuit (front) | Signal error |
| B1233 | An open in the air mix control motor circuit (front) | Signal error |
| B1234 | A short in the air mix control motor circuit (front) | Signal error |
| B1235 | A problem in the air mix control motor circuit, linkage, door, or motor (front) | Signal error |
| B1241 | A problem in the blower motor circuit (front) | Signal error |
| B1244 | An open in the rear air mix control motor circuit | Signal error |
| B1245 | A short in the rear air mix control motor circuit | Signal error |
| B1246 | A problem in the rear air mix control motor circuit, linkage, door, or motor | Signal error |
| B1248 | A problem in the rear mode control motor circuit, linkage, door, or motor | Signal error |
| B2969 | An open in the mode control motor A circuit (front) | Signal error |
| B2970 | A short in the mode control motor A circuit (front) | Signal error |
| B2971 | A problem in the mode control motor A circuit, linkage, door, or motor (front) | Signal error |
| B2972 | An open in the mode control motor B circuit (front) | Signal error |
| B2973 | A short in the mode control motor B circuit (front) | Signal error |
| B2974 | A problem in the mode control motor B circuit, linkage, door, or motor (front) | Signal error |
| B2979 | An open in the A/C pressure sensor circuit | Signal error |
| B2980 | A short in the A/C pressure sensor circuit | Signal error |
| B2983 | A problem in the recirculation control motor circuit, linkage, door, or motor | Signal error |
| B2986 | An open in the recirculation control motor circuit | Signal error |
| U1280 | Communication bus line error (BUS-OFF) | Loss of communication |
| U1281 | Lost Communication with MICU (HVAC control unit) | Loss of communication |
| U128D | Lost communication with gauge control module (HVAC control 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.