Bryant Furnace Code 45.3
Soft lockoutShown as: Major code 45 on the LED (4 short, 5 long); 45.3 on the display
Control failure - EEPROM memory issue on the control board.
Manual wording: “45.3 CONTROL FAILURE - EEPROM memory issue.”
Documented for: 926TC, 912SE
Likely causes, most common first
- Corrupted or failed memory on the control board
What you can safely check yourself
- Turn the furnace off at the service switch for a minute and back on once
When to call a technician
If the code repeats after a power cycle, the control board has to be replaced by a technician.
A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- Installation, Start-up, Operating and Service and Maintenance Instructions - 926TC (Bryant Heating & Cooling Systems, 926TC Preferred Series two-stage, variable-speed ECM multipoise condensing gas furnace) · checked 2026-08-25
- Installation, Start-up, Operating and Service and Maintenance Instructions - 912SE (Bryant Heating & Cooling Systems, 912SE Legacy Line 92% single-stage condensing gas furnace) · checked 2026-08-25