AutoCodes – Ford – P1646 Ford

P1646 Ford Code - Linear O2 Sensor Control Chip Bank 1

Quick Answer

The Powertrain Control Module (PCM) monitors the application-specific integrated circuit that controls and monitors the Heated Oxygen Sensor (HO2S). Common causes include Faulty Powertrain Control Module (PCM). Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1646 Ford indicates Linear O2 Sensor Control Chip Bank 1.
Common causes: Common causes include Faulty Powertrain Control Module (PCM).
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 12,836

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 05, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
Comments
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Code P1646 Ford Description

The Powertrain Control Module (PCM) monitors the application-specific integrated circuit that controls and monitors the Heated Oxygen Sensor (HO2S). The test fails when the PCM detects an internal circuit or communication concern.

OBDII Code P1646 Ford - Linear O2 Sensor Control Chip Bank 1 - AutoCodes.com — P1646 Ford Code - Linear O2 Sensor Control Chip Bank 1

What does this mean?

What are the Possible Causes of the DTC P1646 Ford?

Faulty Powertrain Control Module (PCM)

How to Fix the DTC P1646 Ford?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

Reprogram or update PCM. Check for other DTCs and diagnose those first. Make sure to check for aftermarket performance products before installing a new PCM

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1646 Ford code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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Information for Specific Ford Models

P1646 2006 Ford Fusion — Linear O2 Sensor Control Chip Bank 1
P1646 2007 Ford Fusion — Linear O2 Sensor Control Chip Bank 1
P1646 2008 Ford Fusion — Linear O2 Sensor Control Chip Bank 1
P1646 2009 Ford Fusion — Linear O2 Sensor Control Chip Bank 1
P1646 2010 Ford Fusion — Linear O2 Sensor Control Chip Bank 1
P1646 2011 Ford Fusion — Linear O2 Sensor Control Chip Bank 1
P1646 2012 Ford Fusion — Linear O2 Sensor Control Chip Bank 1

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.