Powertrain, generic (extended)

P2229 Barometric Pressure Sensor A Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2229 reports a barometric sensor A voltage above anything plausible for outside air. Ford's gasoline engines judge more than 4.4 V, an altitude below -1,000 ft, over 5 s; the 2023 diesels use 4.85 V (115 kPa) after 0.5 s. GM's 2018 diesel tables look for contact with a voltage source: over 94.1 % of the 5 V range (115.1 kPa) in 320 of 400 readings, Type B. Mazda bulletin 01-008/20 shows a less obvious cause on the 2018-2020 Mazda6 2.5 turbo: the BARO sensor lives inside the PCM and breathes through a filter hole on its underside. Wax sprayed into the engine bay can seal that hole, so the trapped air builds pressure as the PCM heats up. Mazda replaces the PCM with a reshaped bracket. Ford's 2024 software reports P2226-17 instead; P2228 is the low counterpart.

Likely causes

Breather filter of a PCM-internal BARO sensor clogged (e.g. engine-bay wax, Mazda 01-008/20)
Signal wire of an external sensor shorted to 5 V or battery voltage
Internal fault of the sensor or the control module

Symptoms

  • Check engine light, often only after the engine bay has heated up
  • Auto start-stop deactivated
  • Scan tool shows barometric pressure far above the real value

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–900
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

barometric pressure sensorsensor wiring

Related codes

P2226P2227P2228P2230P222D

References: static.nhtsa.gov, newtonnet.co.uk, fordservicecontent.com, gsi.ext.gm.com.