Superseded. This AD was superseded by AD 2022-24-09. Verify which one applies to your serial and effectivity before any maintenance action.
AD 2021-14-20
Effective 07/20/2021 · Published 07/20/2021
Airworthiness Directives; The Boeing Company Airplanes
Summary
The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 737 airplanes. This AD was prompted by reports of latent failures of the cabin altitude pressure switches. This AD requires repetitive functional tests of the pressure switches, and on- condition actions, including replacement, if necessary. The FAA is issuing this AD to address the unsafe condition on these products.