P1646 - Linear O2 Sensor Control Chip (Bank 1)

2021 Ford Edge SE, 4WDSECTION P1646 - Linear O2 Sensor Control Chip (Bank 1)
DTC DESCRIPTION P1646 - LINEAR O2 SENSOR CONTROL CHIP (BANK 1)

Description:  The PCM monitors the application specific integrated circuit that controls and monitors the universal heated oxygen sensor bank 1, sensor 1 (HO2S11). This DTC sets when the PCM detects an internal circuit or communication concern.
Possible Causes: 
  • Damaged universal HO2S11 wiring
  • Damaged PCM
Diagnostic Aids:  Check for other DTCs and diagnose those first. Check for intermittent universal HO2S wiring concerns. Check the universal HO2S wiring between the PCM and the sensor for damage. Check for aftermarket performance products.
Reprogram or update the calibration. Clear the DTCs, repeat the self-test. If the DTC is retrieved again, install a new PCM. Refer to Flash Electrically Erasable Programmable Read Only Memory (EEPROM).
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test DZ.
RENDER: 1.0x

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