System Diagnosis
Lost Inverter Communication Event (V9+) / Suction Thermistor Range Fault (V8 and earlier). Communication or thermistor fault detected.
Troubleshooting guide for the Bryant Heat Pumps system fault 58.
Loss of comm LEDs, incorrect polarity, or a fault that appears only when indoor and outdoor boards talk.
Board swaps without harness checks can hide the real fault if the wiring path is damaged.
ACLogics walks you through Bryant Heat Pumps diagnostics step-by-step — so you confirm the cause before swapping parts.