P2229

P2229 is the high-input mirror of P2228 — BARO signal voltage above the expected upper threshold, typically over 4.7V on a 5V reference, which would represent a barometric pressure higher than any real-world condition (sea-level high-pressure systems top out near 105 kPa). High input is almost always either a signal wire shorted to the 5V reference or to battery voltage, or a sensor whose internal output stage has failed open and lets the pull-up resistor inside the ECU dominate the reading. Cheapest-first: disconnect the BARO/MAP sensor connector and read the signal wire voltage at the ECU end with key-on engine-off — if it stays pegged at 4.7V+ with the sensor unplugged, the short is in the harness between connector and ECU; if it drops to 0V or floats, the sensor itself is the fault. Check for pushed-back or bridged pins in the sensor connector — green corrosion shorting the signal pin to the 5V reference pin produces exactly this symptom and clears with a pin pick and dielectric grease. Confirm sensor ground integrity — a missing ground can elevate the signal reference. The 15-minute DMM circuit-isolation test almost always points cleanly at either harness, connector, sensor, or PCM without further teardown.

Vehicle-specific patterns: 2010-2017 Ford EcoBoost lineup (F-150 3.5L, Explorer 2.3L/3.5L, Edge Sport 3.5L) throws P2229 with internal-PCM BARO when the PCM's internal pressure sensor output fails open — code is durable across drive cycles and points at PCM replacement ($700-$1,200 with programming). 2007-2013 GM Vortec 5.3L/6.0L throws P2229 from a chafed harness where the MAP/BARO signal wire abrades against the 5V reference at a clip near the intake — splice repair fixes it. 2008-2012 Dodge Ram 5.7L Hemi throws P2229 when the combination MAP/BARO sensor fails internally with the output transistor open — $80-$150 sensor, 0.4 hr labor. 2011-2016 BMW N20/N55 turbo engines throw P2229 from a connector pin issue at the MAP/BARO sensor that BMW addressed via a TSB-style harness retrofit. Estimated repair: $80 to $1,200.