Goodman GMSS960803BN Error Code 2 Flashes: Pressure Switch Stuck Closed
What Does Code 2 Flashes Mean?
Two flashes on the Goodman GMSS960803BN diagnostic LED indicate that the pressure switch circuit is reading closed before the inducer motor has started. The control module performs a pre-start check to confirm the pressure switch is open (its normal resting state). If the switch reads closed at this point, the control module will not initiate the ignition sequence.
Pressure switch contacts that are sticking together are the most frequent cause. The switch is a mechanical device that opens and closes thousands of times over the furnace's life, and the contacts eventually wear. Corrosion or debris on the contacts can also prevent them from separating cleanly after the inducer shuts down.
A wiring short in the pressure switch circuit produces the same symptom. If two wires are touching or a connector has an internal short, the control module sees a completed circuit regardless of the switch's actual position. A technician needs to test the switch independently and inspect the wiring to determine which component has failed.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Pressure switch contacts sticking closed | Most common | ✗ Call a pro → |
| Short in pressure switch circuit wiring | Common | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- The furnace will not start and shows 2 flashes on the LED
- The inducer motor does not run at all
- The pressure switch was replaced but the code remains
✓ Verified against manufacturer service manual — March 2026