P1109 The engine control module saw the barometric pressure sensor signal out of range high
What does P1109 mean on a Honda?
P1109. The engine control module saw the barometric pressure sensor signal out of range high. The engine may idle rough or hesitate because the module cannot read ambient pressure.. This Honda-enhanced code applies to Honda and Acura models that use this code.
Common causes of P1109
- Faulty barometric pressure sensor
- Barometric pressure sensor harness is open or shorted
- Barometric pressure sensor circuit poor electrical connection
- Engine control module software is outdated or incorrect
- Faulty engine control module
How to fix P1109
- Confirm the code with a scan tool and check for related faults
- Inspect the sensor and its connector for corrosion, moisture, and loose pins
- Check the wiring for an open or short between the sensor and the control module
- Test the sensor signal against the factory spec before replacing parts
- Replace the sensor if it fails testing, then clear codes and retest
Sources and review
- Based on one independent source.
- Last updated 2026-10-02.