Powertrain, generic (extended)

P2B7A EVAP System Pressure Sensor/Switch C Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2B7A is the general circuit fault of a third EVAP pressure sensor or switch, C, alongside A (P0450 range) and B (P24D5 range). Each maker assigns the letters itself. Audi V6 and V8 engines (bulletin 2069531, 2022–2025) call it tank ventilation pressure sensor 3, part GX49, and use P2B7A for its electrical fault; the bulletin adds that some control units logged this fault wrongly as P0450. VW uses the code for its fuel tank pressure sensor G400 with NVLD switch on the 2025–2026 Jetta and Taos FWD, where bulletin 01-26-01 blames a too-small orifice in the plug housing. CARB demands that every EVAP input be monitored for circuit faults. Until the fault is fixed, leak tests that rely on this sensor cannot run.

Likely causes

Sensor of an early design (VW G400 with narrow orifice)
Pressure sensor C failed electrically
Open or short in reference, ground or signal wire
Control unit logs a wrong fault entry (Audi bulletin 2069531)

Symptoms

  • Check engine light on
  • EVAP readiness monitor stays incomplete
  • Usually no change in driving behaviour

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–450
Time0.5–2 h

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

Parts involved

evap pressure sensor cwiring harnessecm

Related codes

P2B7BP2B7CP2B7DP2B7EP0450P24D5

References: law.cornell.edu, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.