Goodman Furnace 3 (amber LED) error code
The 3-amp fuse on the integrated control module has blown, cutting 24-volt power to the controls. The furnace cannot run until the fuse is replaced and the short that blew it is found.
Also shown as: 3 amber flashes, three amber flashes, fault code 3 amber, blown fuse, 3 amp fuse
Last updated: September 30, 2026
What causes the 3 (amber LED) error?
- Short in thermostat wiring
- Pinched or chewed low-voltage wires
- Shorted contactor coil or other 24V component
- Power surge
How to fix Goodman 3 (amber LED) — step by step
Work through these in order, from simplest and safest first. Stop as soon as the code clears.
- Look for obvious wire damage
Check visible thermostat wire for nicks, pinches, or chew marks, especially where it passes through walls or near the furnace. - Have a technician find the short
Simply replacing the fuse without finding the short will just blow the new fuse. A technician can isolate the fault with a meter.Safety warning: Never replace the 3A fuse with a higher-rated one. The fuse protects the board and wiring — oversizing it can destroy the control module or start a fire.
When to call a technician
- The replacement fuse blows again
- You find damaged thermostat or control wiring
Frequently asked questions
Where is the fuse?
On the integrated control module inside the furnace's blower/control compartment, next to the low-voltage terminal strip.
Can I replace the fuse myself?
You can, with the power off and an identical 3A automotive-style fuse — but if it blows again, stop and call a technician to find the short.
Sources
Every meaning and fix above was checked against official manufacturer documentation:
FixCode provides general troubleshooting information only — not professional repair advice. If you are unsure about any step, stop and call a qualified technician. Repairs done incorrectly can be dangerous and may void your warranty.