What this code means
P2228 may indicate the PCM is seeing a barometric pressure signal that is lower than expected.
What the vehicle may do
- The vehicle may turn on a warning light.
- The code may be stored without a strong drivability symptom.
- Some control strategies may be affected depending on operating conditions.
Possible fault areas
- A possible barometric pressure signal concern.
- A possible connector or circuit condition related to that signal.
- A possible PCM-side interpretation concern.
Diagnostic path
Opening context
This one is for P2228 on a 2018 to 2025 Honda Accord 2.0 Hybrid. In plain terms, the PCM may be seeing the barometric pressure signal lower than it expects. Depending on when the fault shows up, the vehicle may have a warning light, may limit some control strategies, or may simply store the code with no obvious drivability complaint. Broadly, this can involve the barometric pressure signal the PCM is using, the related connector or circuit condition, or how the PCM is interpreting that input. Before chasing the code, start with the basic system checks and follow a structured diagnostic approach.
Set up the check
Begin by turning the vehicle to the ON mode. At this point, the key part of the diagnosis is not a parts decision. It is confirming what the PCM is seeing for the barometric pressure value.
Confirm whether the failure is duplicated
With the vehicle in ON mode, watch the HDS Baro Sensor value. On USA and Canada models, if that value is less than 371.2 mmHg, the failure is duplicated. On Mexico models, if that value is less than 331.4 mmHg, the failure is duplicated.
Understand the decision
The logic here is straightforward: when the BARO sensor output value is lower than the specified value, the PCM treats that as abnormal and stores P2228. So keep the diagnosis centered on whether the displayed barometric pressure value actually falls below the correct market threshold under the test condition.
Closing takeaway
The takeaway for P2228 is to confirm the low barometric pressure reading first, using the correct threshold for the vehicle’s market, before making any repair decision. For more diagnostic training, visit stepdiagnostics.com.
Final check
Confirm the barometric pressure data value against the correct market threshold before moving deeper into diagnosis.
For more guided automotive diagnostics, visit STEP Diagnostics.
