Error Code Green LED Rapid Flash
Info

Goodman GMEC960803BN Error Code Green LED Rapid Flash: Normal Operation - Fan Call (G)

TL;DR
A rapidly flashing green LED means your Goodman GMEC960803BN is running the blower in fan-only mode because the thermostat is calling for the fan (G terminal). This is normal.
Disclaimer
This article is for informational purposes only and does not guarantee the accuracy or completeness of the information provided. Always turn off power and gas supply before attempting any repairs. If you smell gas, leave immediately and call your gas company. Consult a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk.

What Does Code Green LED Rapid Flash Mean?

A rapid green flash on the Goodman GMEC960803BN's Integrated Control Module signals normal fan-only operation. The thermostat is sending 24 volts to the G terminal, telling the board to run the indoor blower without any heating or cooling.

This happens when the thermostat fan setting is switched to ON (continuous circulation) instead of AUTO, or during the blower-only portion of a cycle. The multi-speed ECM motor runs the blower at its programmed fan-only speed to circulate air. Because green indicates a normal state, a rapid green flash is nothing to troubleshoot.

It is worth knowing the difference from the heating indications: rapid green is fan-only, while amber flashes indicate an active heat call (first or second stage). If you are seeing rapid green when you expected heat, the thermostat is likely calling for fan only rather than for heat.

What You'll Notice

How This Is Diagnosed

No diagnosis is required — this is a normal fan call. If you did not intend continuous fan operation, check the thermostat fan switch: set it to AUTO so the blower runs only during heating or cooling instead of ON, which runs it continuously and produces this rapid green indication.

Contact a licensed HVAC technician if any of these apply:

Frequently Asked Questions

Why is my furnace fan running but no heat is coming out?

A rapid green flash means the furnace is in fan-only mode from a G (fan) call. This is usually because the thermostat fan setting is ON rather than AUTO.

How do I stop the fan from running all the time?

Set the thermostat fan switch from ON to AUTO. In AUTO the blower runs only during a heating or cooling cycle instead of circulating air continuously.

Sources

  1. *MEC96 & *CEC96 Two-Stage Gas Furnaces

✓ Verified against manufacturer service manual — March 2026