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Home >> Ford >> 2021 >> Edge ST-Line, FWD >> Repair and Diagnosis >> Quick Lookups >> DTC Index >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> Diagnostic Trouble Code (DTC) Charts And Descriptions >> P0135 - O2 Sensor Heater Circuit (Bank 1 Sensor 1)
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P0135 - O2 Sensor Heater Circuit (Bank 1 Sensor 1)

DTC DESCRIPTION P0135 - O2 SENSOR HEATER CIRCUIT (BANK 1 SENSOR 1)

Description:  This DTC sets when an open or short circuit is detected or the heater current draw exceeds a calibrated limit.
Possible Causes: 
  • UO2SHTR11 circuit open (if equipped)
  • UO2SHTR11 circuit short to voltage (if equipped)
  • HTR11 circuit open (if equipped)
  • HTR11 circuit short to voltage (if equipped)
  • VPWR circuit open
  • Low battery voltage
  • Water in the harness connector
  • Corrosion
  • Incorrect connections
  • Damaged universal heated oxygen sensor bank 1, sensor 1 (HO2S11) heater (if equipped)
  • Damaged HO2S11 heater (if equipped)
Diagnostic Aids:  Inspect the connectors for signs of damage, water intrusion or corrosion.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
EcoSport 1.5L, KA GO to Pinpoint Test DW.
All others GO to Pinpoint Test DZ.