Goodman furnace rapid flashing: Reversed 115V Polarity or Poor Ground
Professional repair
Why is the light on my Goodman furnace flashing continuously? Official: the 115-volt line polarity is reversed or the unit ground is poor. The furnace won't heat until wiring is corrected.
Before you touch anything: the six signs that mean stop troubleshooting and call a pro →
Line-voltage wiring — electrician or HVAC tech.
What causes it (in order of likelihood)
- Hot/neutral reversed at the furnace or outlet TECH
- Poor unit 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
Why is the light on my Goodman furnace flashing continuously?
Official: the 115-volt line polarity is reversed or the unit ground is poor. The furnace won't heat until wiring is corrected.
How do I fix Goodman furnace rapid flashing?
This is line-voltage wiring. Don't open panels or test wiring yourself; call an electrician or HVAC technician.
How much does it cost to fix Goodman furnace rapid flashing?
Cost depends on where the wiring problem is, at the furnace or the supply, and whether grounding needs correcting. Ask for a quote once the wiring fault has been located.
Applies to
GMS8 · GDS8 · GHS8 · GMSS96 · GMH8 · GDH8
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 GMS8/GDS8/GHS8 Service Manual (RS6612006), p.44 — “CONTINUOUS / Polarity of 115 volt AC / Poor unit ground”
Last verified 2026-07-06 · page updated 2026-10-03 · how we verify
Other Goodman furnace codes
These links include other Goodman model families. Code meanings can change by model and control board, so confirm your model and service manual before using a definition.
| Pattern | Meaning |
|---|---|
| 8 flashes | Igniter Circuit Fault or Poor Ground |
| E0display E0 | Ignition Lockout (E0) |
| 7 flashes | Low Flame Sense Signal |
| E1display E1 | Low-Stage Pressure Switch Stuck Closed (E1) |