Vehicle applicability: This diagnostic supplement covers multiple Ford vehicles and engines. Follow the application named in the source below. Some references apply to vehicles other than Mustang.
4-132 Powertrain DTC Charts and Descriptions
Diagnostic Trouble Code (DTC) Charts and Descriptions
P2243 - O2 Sensor Reference Voltage Circuit Open - Bank 1, Sensor 1 (Continued) Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test DZ.
P2247 - O2 Sensor Reference Voltage Circuit Open - Bank 2, Sensor 1
Description: This DTC sets when a concern is detected with the circuit used to determine the oxygen content in the exhaust
gas.
Possible Causes: • UO2S21 circuit open
• Damaged universal heated oxygen sensor bank 2, sensor 1 (HO2S21)
Diagnostic Aids:
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test DZ.
P2251 - O2 Sensor Negative Current Control Circuit Open - Bank 1, Sensor 1
Description: This DTC sets when a concern is detected with the circuit used to determine the oxygen content in the exhaust
gas.
Possible Causes: • UO2SGREF11 circuit open
• Damaged universal heated oxygen sensor bank 1, sensor 1 (HO2S11)
Diagnostic Aids:
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test DZ.
P2254 - O2 Sensor Negative Current Control Circuit Open - Bank 2, Sensor 1
Description: This DTC sets when a concern is detected with the circuit used to determine the oxygen content in the exhaust
gas.
Possible Causes: • UO2SGREF21 circuit open
• Damaged universal heated oxygen sensor bank 2, sensor 1 (HO2S21)
Diagnostic Aids:
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test DZ.
P2270 - O2 Sensor Signal Stuck Lean - Bank 1, Sensor 2
Description: The heated oxygen sensor bank 1, sensor 2 (HO2S12) is forced rich and lean and monitored by the PCM. This
DTC sets when the PCM does not detect the output of the HO2S12 in a calibrated amount of time.
Possible Causes: • Pinched, shorted, and corroded wiring and pins
• Crossed HO2S12 wires
• Exhaust leaks
• Contaminated HO2S12
• Damaged HO2S12
Diagnostic Aids:
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test H.
P2271 - O2 Sensor Signal Stuck Rich - Bank 1, Sensor 2
Description: The heated oxygen sensor bank 1, sensor 2 (HO2S12) is forced rich and lean and monitored by the PCM. This
DTC sets when the PCM does not detect the output of the HO2S in a calibrated amount of time.
Possible Causes: • Pinched, shorted, and corroded wiring and pins
2016 Powertrain Control/Emissions Diagnosis, Gasoline Engines, 3/2015
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.