Powertrain, generic (extended)

P2244 O2 Sensor Reference Voltage Performance (Bank 1 Sensor 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2244 stands for a plausibility fault on the reference voltage side of the bank 1 upstream wide-band sensor: the Nernst-cell signal is electrically intact and within limits, but behaves in a way that does not fit the operating state, for instance offset or too slow. No manufacturer documents P2244 publicly. Ford treats this lead only as an open circuit (P2243) and books shorts on any sensor wire under P0131/P0132; GM, Saab and VW likewise publish only the open-circuit code. Bosch specifies the Nernst cell at a nominal 300 ohms and a load of at most 250 microamps, so ageing or contamination shows up as a shifted reading. CARB requires fuel-control sensors to be checked for implausible values as well as circuit faults. P2243 is the open line, P2245/P2246 low/high, P2248 bank 2.

Likely causes

Aged or contaminated wide-band sensor (oil ash, silicone, coolant)
High resistance in the reference voltage wire or connector
Exhaust leak ahead of the sensor distorting the reading

Symptoms

  • Check engine light
  • Slightly higher fuel consumption
  • Possible failed emissions test

Repair estimate

DifficultyMediumDIY possible
Parts and labour€80–400
Time0.5–2 h

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

Parts involved

oxygen sensor bank1 sensor1oxygen sensor wiringecm

Related codes

P2243P2245P2246P2248P223CP0133

References: law.cornell.edu, bosch-motorsport.com, newtonnet.co.uk.