Goodman GMEC960803BN Error Code Green LED Solid On: Standby
What Does Code Green LED Solid On Mean?
A solid green LED on the Goodman GMEC960803BN indicates the furnace is in standby mode. The integrated control module has power, has completed its self-diagnostic checks, and is waiting for a signal from the thermostat to begin a heating or cooling cycle.
The GMEC960803BN uses a tri-color LED diagnostic system (green, amber, red) where green indicates normal operating states and red indicates faults. A solid green light is the most basic normal state — the furnace is idle and ready. You will see this when no heating, cooling, or fan calls are active.
If your home is not reaching the desired temperature and the furnace shows a solid green standby light, the issue is likely with the thermostat or its wiring. Verify the thermostat is set to the correct mode (heat or cool), the setpoint is appropriate, and the system switch is not in the OFF position. If the thermostat appears to be calling for heat but the furnace remains in standby, the thermostat wiring may need professional inspection.
- If the furnace stays in standby and never fires when the thermostat is calling for heat — the wiring between thermostat and furnace may have an open or loose connection
✓ Verified against manufacturer service manual — March 2026