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U0609 Lost Communication With Manifold Absolute Pressure/Barometric Pressure Sensor

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

A digital manifold pressure sensor sends pressure, often with an intake temperature value, as SENT frames; chips built for this, such as Infineon's KP276, add a status nibble with error flags and a CRC to every frame. U0609 is stored when those frames stop arriving or cannot be used. Ford's 2023 diesel summary defines it for the SENT MAP sensor: the SENT driver flags a communication fault, the data line hangs at low voltage, or the sensor flags an internal fault, checked continuously and registered after 5 s. P0105 is the separate code for a sensor whose status bit or reading is implausible. The NHTSA index lists a 2023 Audi RS 6 Avant bulletin covering U0609 with U060A. Load and boost then run on substitute values.

Likely causes

SENT line stuck low, open or chafed, or supply/ground missing
Sensor reports an internal fault (moisture, oil or soot ingress)
Corroded or loose sensor connector

Symptoms

  • Check engine light
  • Reduced power or limited boost
  • Rough running or harder starting at altitude

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–300
Time0.3–1.5 h

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

Parts involved

map baro sensorsensor wiring

Related codes

P0105P0106P0107P0108U060AU067F

References: fordservicecontent.com, infineon.com, law.cornell.edu.