P2227 Code: Barometric Pressure Circuit Range/Performance
The P2227 code means the barometric pressure (BARO) sensor is giving a reading that makes electrical sense but does not match what the computer expects. The main effect is a less precise mixture and less power, especially at altitude. You can keep driving, but the engine may feel a bit down on power.
- Severity
- Medium
- Can I keep driving?
- Yes, no immediate risk
- Estimated cost
- $40 to $300
- Difficulty
- Medium
- System
- Air and Fuel
- Applies to
- All OBD2 vehicles
On this page
What the P2227 code means
The barometric pressure sensor, which is the circuit the P2227 code monitors, measures atmospheric pressure. The computer uses it to correct the mixture and the turbo for altitude. On many vehicles it sits inside the computer itself, and on others it is in the engine compartment or built into the MAP sensor.
The sensor gets a 5 V reference and a ground from the computer and returns a signal of roughly 0.5 to 4.5 V. A range or performance fault means the sensor is measuring, but measuring wrong, or that there is a real abnormal condition.
At sea level it reads about 100 kPa (14.5 psi), and the pressure drops with altitude. At 2,500 meters (about 8,200 ft) it is around 75 kPa (about 10.9 psi). A sensor guide shows how to test the MAP sensor, which works the same way.
This kind of fault is usually not solved with a multimeter alone, because electrically everything looks fine. You have to compare what the part says with reality: use a gauge, a thermometer, a tachometer, or command the component with the scan tool and see whether the physical result matches the order.
P2227 code symptoms
- Check engine light on.
- Less precise mixture and power, especially at altitude.
Likely causes of the P2227 code
- Aged or out-of-calibration sensor. It gives believable readings that are wrong.
- Real abnormal condition. The system is genuinely operating outside normal.
- High resistance in the connector from corrosion, which shifts the reading.
- Damaged or blocked port, hose or tone wheel, depending on the type of sensor.
How to diagnose the P2227 code step by step
- Read the sensor value on the scan tool and compare it with what you expect.
- Inspect the connector for corrosion, water or loose pins.
- Check power and ground with the key on: correct reference voltage and less than 0.1 V drop on the ground.
- Measure the signal with the connector plugged in and see whether it changes with the conditions.
- Do a wiggle test on the wiring with the scan tool in graph mode.
- Check the continuity of each wire to the computer (less than 1 ohm).
How to fix the P2227 code
- Repair the connector or the wiring.
- Replace the sensor if the tests confirm it is bad.
- Correct the real condition if there is one.
- Clear the codes and verify with a road test.
After the repair, compare the BARO reading with the MAP reading with the key on and the engine off. If the P2227 code stays away and the two readings agree, the job is done.
Technical reference data
- At sea level: about 100 kPa (14.5 psi), with a signal near 4 to 4.5 V.
- The BARO reading and the MAP reading should match with the engine off and the key on.
- These are reference values only: check the manufacturer data for your vehicle.
Brand-specific notes
On many vehicles the sensor sits inside the computer. In that case rule out everything else before you replace the computer. On turbo diesels it is usually a separate sensor.
P2227 on Toyota
On many Toyota models the sensor is inside the computer, so rule out everything else before replacing it.
P2227 on Honda
On many Honda models the sensor is inside the computer, so rule out everything else before replacing it.
P2227 on Ford
On many Ford models the sensor is inside the computer, so rule out everything else before replacing it.
Questions about the P2227 code
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