GR9S96

This board

Self-diagnostic IFC · single 7-segment (Seg3→Seg2→Seg1)

• Read left to right. This card prints EE0 / EE1 / EE2 — three characters, E E and a digit. That is not GR9T96 E0 / E1 / E2, even though the physics rhyme.
• EE1 (E E 1) is PS stuck closed. E11 (E 1 1) is open rollout. Those are different codes. Write all three characters.
• One pressure switch only. There is no E8/E9 high-fire pair on this IFC.
• A2L pair codes (EAF, EAL, EAS, Ear) only apply when this furnace is tied to an R-32 / A2L outdoor. Ignore them on R-410A pairs.

Sequence

1. W. IFC proves limits/rollout closed, starts the single-speed inducer.
2. Prove PS. The only pressure switch must close. Already closed with inducer off → EE1. Never closes → EE2.
3. HSI / valve. Nitride warm-up, then the single solenoid. Open igniter → EEn. Failures stack toward EE0.
4. Blower. Heat-on delay, then the 9-speed ECM on the selected heat tap. Wrong tap is the silent EE3.

Faults on this IFC

• EEE

  Internal / IRQ loss

  lockout

  IFC internal fault or interrupt loss.

  • Power cycle once. Repeat EEE = board, after 120/24 and the door switch are proven.
• EE0

  Retry / recycle lockout

  lockout

  Too many failed ignition attempts or flame losses on this call.

  • Watch one full try: inducer, HSI, valve, flame, µA.
  • Gas, rod, ground. Do not keep resetting.
• EE1

  PS stuck closed

  lockout

  The only pressure switch is made with the inducer off. Display is E E 1 — not E11 (rollout).

  • Unplug the PS. If the code changes, switch is welded or the hose is holding residual draft.
  • Hose downhill to the collector? Water fakes a closed switch.
• EE2

  PS open

  lockout

  Inducer is on and the only switch will not close. The winter 96% call on this new 7-seg single.

  • Inducer 120 VAC and spinning.
  • Collector, trap, PVC intake/exhaust, ice, wind.
  • Hose on the only tap. There is no high-fire hose to move.
• EE3

  Open high limit

  warn

  Primary limit opened. Airflow or overfire.

  • This is a 9-speed ECM. Read the heat tap before you replace a limit.
  • Filter, coil, TES vs the GR9S96 blower chart for this cabinet (A/B/C/D).
  • Manifold vs plate — overfire trips limits with a clean filter.
• EE4

  Flame when valve should be off

  hazard

  Rod sees flame with the solenoid de-energized.

  • Shut the gas cock. If flame stays, leaking valve — replace, do not jump.
• EE5

  Open fuse

  warn

  24 V fuse on the IFC is open.

  • Short on W, Y, G, humidifier, EAC.
  • Unplug the tstat harness and replace the fuse.
• EE6

  Low flame signal

  warn

  Flame present, µA below threshold.

  • Clean rod with a non-scratch pad.
  • Chassis ground, manifold, LP conversion.
• EEL

  Ignitor relay fault

  lockout

  IFC did not see the igniter circuit behave as commanded.

  • Igniter ohms cold, 120 VAC during warm-up, cracked nitride.
• EEA

  Reversed polarity / ground

  lockout

  L1/N reversed or chassis ground missing.

  • Hot and neutral at the IFC. Burner-box ground screw.
• EEb / EEC

  Gas valve circuit

  lockout

  Internal (EEb / ASME) or external (EEC) gas-valve electrical fault.

  • Valve coil ohms, 24 VAC at the harness during trial.
• E11

  Open rollout

  hazard

  Display is E 1 1 — not EE1 (PS closed). Manual-reset rollout. Treat as flame outside the exchanger until proven otherwise.

  • Primary exchanger, burner alignment, crossover, blocked secondary / condensate / flue.
  • Reset only after the cause is fixed.
• EEn

  Ignitor open

  lockout

  Igniter circuit measures open.

  • Ohms at the igniter plug, then at the IFC.
  • Harness rub-through on the collector.
• EEH

  Twin error

  lockout

  Twinning miswire or twin terminal active on a standalone unit.

  • If not twinned, nothing should be on the TWIN terminal.
• E10

  Grounding error

  lockout

  IFC failed its ground check (sister to EEA).

  • Green ground to cabinet and IFC. Painted screw, missing star washer.
• EbL / EbU

  Circulator current

  lockout

  9-speed ECM current too low (EbL) or unexpected (EbU).

  • Harness seated at motor and IFC. A half-seated tap plug throws these.
  • Locked rotor, wet winding, or a PSC motor someone hung on this IFC.
• EAF / EAL / EAS / Ear

  A2L mitigation

  hazard

  Leak / comm / relay alarm from the A2L board when paired with R-32 or R-454B outdoor.

  • Only valid on A2L pairs. On 410A this is a miswired mitigation harness.

Workflows

Test points

Display

Three characters left to right. EE1 ≠ E11.

Pressure switch

One NO switch. Closed only with inducer up.

9-speed heat tap

Match the installer’s tap to the rise range on the rating plate (typically 35–65°F).

Flame rod

µA per this door card — not the GMSS96 flash sticker.

Gotchas

• Warehouse ‘Goodman 96% IFC’ often ships a GR9T96 two-stage board or a GMSS96 flash board. The motor and the door card have to match.
• EE1 is PS closed. E11 is rollout. Reading only the last digit gets someone hurt.
• GMSS96 3-flash videos do not apply. This board does not flash.

Related plates

• amana-ar9s96 — Amana single-stage 9-speed cousin. One PS, 9-speed taps — but the door is 0140F20003-B E0–E7, not this EE0/EE1/EE2 card.
• goodman-gr9t96 — Two-stage 9-speed cousin. Dual PS, E1/E2 vs E8/E9. Wrong high-fire codes for this cabinet.
• goodman-gmss96 — Older single-stage flash 96%. Same one-PS physics, LED 1–9 instead of EE-codes.
• goodman-gms80 — 80% single-stage flash. Same 3-flash idea, metal vent, no collector.