Goodman GMS / GDS / GHS / GKS furnace fault codes
Every diagnostic code published for the GMS series — 10 of them — taken from the manufacturer's own per-model fault code database rather than from a general table.
Codes differ between models from the same manufacturer, which is why this list is worth reading in preference to a brand-wide one. On this model 6 flash means rollout switch has tripped; on the GMSS9 the same signal means rollout limit open, or control module fuse blown. Its 10 codes put it 9th of 10 Goodman lists by length, between the GCVM97 at 43 and the GMP at 8. The same board is sold as Goodman GDS / GHS / GKS, with the same code list.
GMS fault codes
| What the LED shows | What it means |
|---|---|
| 1 flash | Lockout after too many failed ignition attempts |
| 2 flashes | Pressure switch is closed when it should be open |
| 3 flashes | Pressure switch will not close |
| 4 flashes | High limit switch is open — the furnace is overheating |
| 5 flashes | Flame detected when no flame should be present |
| 6 flashes | Rollout switch has tripped |
| 7 flashes | Flame signal is too weak |
| LED off | No power to the furnace, or an internal control fault |
| rapid flashing | Reversed 115 volt polarity, a grounding problem, or an open igniter circuit |
Codes that are not faults
These 1 indications mean the furnace is doing something normal — running a stage, moving air for cooling, or sitting idle. They are listed separately so they do not get counted as problems.
| What the LED shows | What it means |
|---|---|
| continuous on | Normal operation — no fault stored |
Other models with their own code list
- Goodman GMH / GCH / GCSS9 / GDH / GME and Amana ACSS9 / AMH — 11 codes
- Goodman GCVC96 / GCVC8 / GCVC95 / GMVC95 and Amana ACVC95 / ACVC96 / AMVC95 / AMVC96 — 31 codes
- Goodman GCVM97 / GCVM96 / GMVM96 / GMVM97 and Amana ACVM96 / ACVM97 / AMVM96 / AMVM97 — 43 codes
- Goodman GMEC96 and Amana AMEC96 — 24 codes
- Goodman GMSS9 and Amana AMSS9 — 11 codes
- Goodman GMV8 and Amana AMV8 / AMV9 — 12 codes
- Goodman GMP / GMN / GMNT / GMPE / GMPH / GMPN / GMPV / GMT — 8 codes
- Goodman GMV9 — 11 codes
- Goodman GMVC96 / GMVC8 — 32 codes
What the fix costs
For what a technician visit and this kind of repair typically runs, see the furnace repair cost guide.
What this looks like
From the outside, this usually shows up as the vents blowing cold air on a heat call — that walkthrough covers what to check in order, and when it stops being a homeowner job.