What this code means
P2229 means the PCM may be seeing a barometric pressure sensor signal that is higher than expected.
What the vehicle may do
- The vehicle may turn on a warning light.
- The PCM can use the BARO signal as part of load and atmospheric pressure calculations.
- Driveability symptoms may vary depending on when the signal concern occurs.
Possible fault areas
- Possible BARO signal concern.
- Possible circuit or connector concern.
- Possible PCM input or signal interpretation concern.
Diagnostic path
Opening context
On this 2016 through 2024 Honda Civic with the 2.0 gas engine, P2229 is for the barometric pressure sensor circuit reading high. In plain terms, the PCM is seeing a BARO signal that may be higher than it expects. Depending on when it happens, the vehicle may have a warning light, and it can affect how the PCM interprets load and atmospheric pressure. Broad possible areas can include the BARO signal, its circuit or connection, and how that signal is being read by the PCM. Before getting into the code-specific check, start with the basic system checks and follow a structured diagnostic approach.
What sets the code
The logic behind this code is straightforward: if the BARO sensor output value is higher than the specified value, the PCM determines there is an abnormality and stores P2229. So for this one, we are not starting with a parts call. We are first trying to duplicate the high BARO reading under the proper key-on condition.
Code-specific check
Turn the vehicle to the ON mode. With the scan tool connected, look at the HDS Baro Sensor value. If the HDS Baro Sensor value is more than 864.1 mmHg, the failure is duplicated. That is the decision point given for this diagnostic path.
If the value does not duplicate
If the BARO value is not more than 864.1 mmHg during this check, do not jump to a repair. Pause, recheck the earlier diagnostic path, make sure the vehicle is in the correct ON mode condition, and avoid guessing beyond the information this path gives you.
Verification and takeaway
Keep verification separate from the code-specific test. After any valid correction made outside this limited path, verify the repair and confirm the code stays gone. The takeaway on P2229 is simple: key ON, watch the HDS Baro Sensor value, and use more than 864.1 mmHg as the point where the high BARO failure is duplicated. For more diagnostic training, visit stepdiagnostics.com.
Final check
For this diagnostic path, duplicate the concern by checking the HDS Baro Sensor value with the vehicle in ON mode.
For more guided automotive diagnostics, visit STEP Diagnostics.
