Powertrain, generic (extended)

P2BF7 Exhaust Flow Control Valve A Position Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2BF7 is set when the position feedback of exhaust valve A rises above its plausible maximum. Electrically that points to the signal line touching the sensor reference or battery voltage, or to a lost sensor ground, which lets the input float up to its pull-up level. Deutz assigns P2BF7 with failure type 12 to a flap voltage that is too high or shorted to positive on its MD1 industrial engines, the counterpart to P2BF6. Mazda covers it for the 2024 CX-5 in service alert SA-056-23 together with P2BF5 and P2BF6, which concern the exhaust shutter valve used with cylinder deactivation; thresholds are not published there. CARB requires out-of-range checks on such inputs. Before condemning the valve, measure its ground and signal line with the actuator unplugged.

Likely causes

Open sensor ground letting the signal float high
Signal wire shorted to reference or battery voltage
Position sensor in the valve assembly failed

Symptoms

  • Check engine light on
  • Exhaust flap held in its default position
  • Exhaust sound no longer changes as expected

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

exhaust flow control valve awiring harnessecm

Related codes

P2BF4P2BF5P2BF6P2BFFP26C7

References: serdia.deutz.com, static.nhtsa.gov, law.cornell.edu.