Error Code Amber 4 Flashes
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Goodman GMEC960803BN Error Code Amber 4 Flashes: Y Present With No G Call, Y1 Present With No G Call

TL;DR
Your Goodman GMEC960803BN is receiving a cooling call (Y terminal) without the required fan signal (G terminal). This is a thermostat wiring problem that requires professional repair.
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 Amber 4 Flashes Mean?

Four amber flashes on the Goodman GMEC960803BN control board indicate that the control module is detecting a Y (cooling) signal without a G (fan) signal from the thermostat. Under normal operation, a cooling call always includes a fan call — the blower must run to distribute conditioned air. Receiving Y without G is an invalid thermostat signal combination.

This code is typically caused by incorrect thermostat wiring. If a thermostat was recently installed or replaced, the wires may be connected to the wrong terminals. A malfunctioning thermostat relay board can also send a cooling signal without activating the fan relay.

The furnace will not operate in this mode to prevent the air conditioning system from running without airflow, which could cause the evaporator coil to freeze. Once the wiring is corrected so that G is present whenever Y is called, the system will function normally.

Common Causes

Cause Likelihood DIY?
Improperly connected thermostat wires Most common ✗ Call a pro →
Faulty thermostat Common ✗ Call a pro →

When to Call a Professional

Contact a licensed HVAC technician if:

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Sources

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

✓ Verified against manufacturer service manual — March 2026