!!
critical Trane

Error Code E11

Gas valve not energized when it should be (e.g., failed to establish flame in first try). Retry exceeded condition.

? What Causes This

Faulty gas valve, igniter failure, or electrical wiring issues.

How to Fix It

Shut off power and check electrical connections. Replace faulty components such as the gas valve or ignition system.

Source: page 26 of the official manual

From the manual

Manual page 26 — Trane error E11

This error code appears in:

Trane S9x1