AutoCodes – Ford – P0642 2006 Ford Fusion

P0642 2006 Ford Fusion Code - Sensor Reference Voltage 'A' Circuit Low

Quick Answer

The control module has 2 internal 5-volt reference buses called "5-volt reference 1" and"5-volt reference 2". Common causes include Faulty Engine Control Module (ECM), ECM harness is open or shorted, ECM circuit poor electrical connection. 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: P0642 2006 Ford Fusion indicates Sensor Reference Voltage 'A' Circuit Low.
Common causes: Common causes include Faulty Engine Control Module (ECM), ECM harness is open or shorted, ECM circuit poor electrical connection.
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 4,319

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 May 01, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0642 2006 Ford Fusion Description

The control module has 2 internal 5-volt reference buses called "5-volt reference 1" and"5-volt reference 2". Each reference bus provided 5-volt reference circuit for more than one sensor. Therefore, a fault condition on one 5-volt reference circuit will affect the other 5-volt reference circuits connected to the reference bus. The control module monitors the voltage on the 5-volt reference buses.

OBDII Code P0642 2006 Ford Fusion - Sensor Reference Voltage 'A' Circuit Low - AutoCodes.com — P0642 2006 Ford Fusion Code - Sensor Reference Voltage 'A' Circuit Low

What does this mean?

What are the Possible Causes of the DTC P0642 2006 Ford Fusion?

Faulty Engine Control Module (ECM)
ECM harness is open or shorted
ECM circuit poor electrical connection
Shorted sensor on 5 volt circuit

How to Fix the DTC P0642 2006 Ford Fusion?

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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0642 2006 Ford Fusion 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.

Need more information about the P0642 2006 Ford Fusion code?

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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.

Frequently Asked Questions about P0642 2006 Ford Fusion Code

1. What are the common symptoms of OBDII code P0642 on a 2006 Ford Fusion?

- Common symptoms include the Check Engine light illuminating, rough idling, poor fuel efficiency, and potential stalling of the vehicle.

2. What does the OBDII code P0642 'Sensor Reference Voltage 'A' Circuit Low' mean for a 2006 Ford Fusion?

- This code indicates that the voltage signal from the sensor reference circuit 'A' is below the normal operating range, potentially causing issues with sensor readings.

3. What are the possible causes of OBDII code P0642 on a 2006 Ford Fusion?

- Possible causes include a faulty sensor, damaged wiring or connectors in the sensor circuit, a defective Engine Control Module (ECM), or a low battery voltage.

4. How can I diagnose the OBDII code P0642 on my 2006 Ford Fusion?

- To diagnose this code, you can use a diagnostic scanner to retrieve the specific trouble code, check the sensor reference voltage with a multimeter, inspect the wiring and connectors for any damage, and perform a battery voltage test.

5. Can I continue driving my 2006 Ford Fusion with OBDII code P0642?

- It's not recommended to continue driving with this code present, as it can lead to potential engine performance issues and further damage if left unresolved.

6. How can I repair OBDII code P0642 on my 2006 Ford Fusion?

- Repair options include replacing the faulty sensor, repairing or replacing damaged wiring or connectors, resetting the ECM, or addressing any underlying battery voltage issues.

7. Is it necessary to reset the trouble codes after repairing OBDII code P0642 on a 2006 Ford Fusion?

- Yes, it's important to clear the trouble codes using a diagnostic scanner after performing repairs to reset the ECM and ensure the issue has been resolved.

8. Can a DIY enthusiast fix OBDII code P0642 on a 2006 Ford Fusion?

- Depending on the troubleshooting skills and tools available, a DIY enthusiast may be able to diagnose and repair this code, especially if it involves simple tasks like sensor replacement or wiring repairs.

9. How much does it typically cost to repair OBDII code P0642 on a 2006 Ford Fusion at a mechanic?

- The cost of repairing this code can vary based on the underlying issue, but it may range from $100 to $300, including parts and labor, at a mechanic's shop.

10. Will OBDII code P0642 cause my 2006 Ford Fusion to fail an emissions test?

- Yes, if this code is present during an emissions test, it can cause your vehicle to fail due to potential issues with sensor readings and emission control systems.