DTC P1646 - Linear O2 Sensor Control Chip (Bank 1)

2018 Ford Fusion Platinum HybridSECTION DTC P1646 - Linear O2 Sensor Control Chip (Bank 1)
P1646 - LINEAR O2 SENSOR CONTROL CHIP (BANK 1)

Description:  This DTC sets when an internal universal HO2S circuit or communication concern is detected in the PCM.
Possible Causes: 
  • Damaged PCM
Diagnostic Aids:  Reprogram or update the calibration. Check for other DTCs and diagnose those first. Make sure to check for aftermarket performance products before installing a new PCM. 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) , Programming the VID Block for a Replacement PCM.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All Refer to the Description, Possible Causes and Diagnostic Aids for the DTC.
RENDER: 1.0x

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • Brakes feel soft, pull hard to one side, or make grinding noises.
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