Goodman GMEC96 furnace 9 red flashes: Grounding Fault or Reversed Polarity
Professional repair
What do 9 red flashes mean on a Goodman GMEC96 furnace? The GMEC96 wiring legend assigns nine red flashes to improper grounding or reversed 115-volt polarity. The control will not operate correctly until the line wiring is corrected.
Before you touch anything: the six signs that mean stop troubleshooting and call a pro →
Have an HVAC technician or electrician verify polarity and grounding. This is line-voltage work.
What causes it (in order of likelihood)
- Hot and neutral reversed at the furnace supply TECH
- Loose or missing equipment ground TECH
Parts for this code
No specific part number is verified for this code — it typically points at wiring, power, a blown fuse, or communication between components rather than one standard replacement part. If your diagnosis does land on a replaceable component, match its part number against your model's parts list before ordering.
Questions about this code
What do 9 red flashes mean on a Goodman GMEC96 furnace?
The GMEC96 wiring legend assigns nine red flashes to improper grounding or reversed 115-volt polarity. The control will not operate correctly until the line wiring is corrected.
How do I fix Goodman GMEC96 furnace 9 red flashes?
The control won't operate correctly until the line wiring is fixed. Don't open panels or test wiring; have an HVAC technician or electrician verify polarity and ground.
How much does it cost to fix Goodman GMEC96 furnace 9 red flashes?
Cost depends on whether the supply wiring is reversed or the ground is loose or missing, and where the problem sits. An inspection comes first.
Applies to
GMEC96
Different Goodman generations use different code maps. If your series isn't listed, don't assume this meaning — check your blower-door label.
Verified against Goodman GMEC96 Service Manual, p.53
Last verified 2026-07-06 · page updated 2026-10-03 · how we verify
Related Goodman furnace codes
These codes use the same gmec96 tri-color control — red fault flashes system.