DTC P0155 - O2 Sensor Heater Circuit (Bank 2 Sensor 1)

2021 Ford Edge SE, 4WDSECTION DTC P0155 - O2 Sensor Heater Circuit (Bank 2 Sensor 1)
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P0155 - O2 SENSOR HEATER CIRCUIT (BANK 2 SENSOR 1)

Description:  This DTC sets when an open or short circuit is detected or the universal heated oxygen sensor bank 2, sensor 1 (HO2S21) heater current draw exceeds a calibrated limit.
Possible Causes: 
  • UO2SHTR21 circuit open
  • UO2SHTR21 circuit short to voltage
  • VPWR circuit open
  • Low battery voltage
  • Water in the harness connector
  • Corrosion
  • Incorrect connections
  • Damaged universal HO2S21 heater
Diagnostic Aids:  Inspect the connectors for signs of damage, water intrusion or corrosion.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST DZ .
RENDER: 1.0x

NO RELATED

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