Goodman GMSS920803BN Error Code 2 Flashes: Pressure Switch Stuck Closed
What Does Code 2 Flashes Mean?
Two flashes on the Goodman GMSS920803BN diagnostic LED indicate that the pressure switch circuit is closed when it should be open. Before starting the ignition sequence, the control module verifies that the pressure switch is in its default open state. If the switch reads closed before the inducer motor starts, the control module blocks the entire startup process.
The most common cause is worn pressure switch contacts that are physically sticking together. Over time, the internal contacts in the switch can corrode or develop a film that prevents them from separating cleanly. Once the contacts stick, the switch stays closed regardless of the actual draft pressure.
A short circuit in the pressure switch wiring can produce the same symptom. If two wires in the circuit are touching or a connector has failed, the control module sees a closed circuit even though the switch itself may be working correctly. A technician will need to test the switch and wiring to isolate the fault.
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 the LED shows 2 flashes
- The inducer motor does not start at all
- A pressure switch replacement did not resolve the issue
✓ Verified against manufacturer service manual — March 2026