AutoCodes – Mercury – P1400 Mercury

P1400 Mercury Code - Differential Pressure Feedback Electronic Sensor Circuit Low Voltage

Quick Answer

The purpose of the Exhaust Gas Recirculation (EGR) system on your engine is to limit oxides of nitrogen (NOx) emissions. Common causes include Differential Pressure Feedback Electronic Sensor harness is open or shorted, Differential Pressure Feedback Electronic Sensor circuit poor electrical connection, Faulty Differential Pressure Feedback Electronic Sensor. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

What it means: P1400 Mercury indicates Differential Pressure Feedback Electronic Sensor Circuit Low Voltage.
Common causes: Common causes include Differential Pressure Feedback Electronic Sensor harness is open or shorted, Differential Pressure Feedback Electronic Sensor circuit poor electrical connection, Faulty Differential Pressure Feedback Electronic Sensor.
Severity: Moderate - service should be scheduled soon.
Can I drive?: The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

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Code Popularity 16,995

How popular is this code, among other codes? Low

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 22, 2020

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P1400 Mercury Description

The purpose of the Exhaust Gas Recirculation (EGR) system on your engine is to limit oxides of nitrogen (NOx) emissions. This is done by redirecting small amounts of exhaust gas back through the upper intake to get mixed in with the air/fuel charge. The resultant diluted air/fuel mixture (i.e., less oxygen per cubic foot) burns cooler and combustion chamber temperatures are reduced accordingly, thereby lowering NOx emissions.
The Ford DPFE/EGR system is controlled by the Powertrain Control Module (PCM). The system employs an EGR Valve, an Electronic Vacuum Regulator (EVR), and a Delta Pressure Feedback EGR sensor (DPFE).
The DPFE Sensor measures EGR flow across an orifice located inside the special EGR Tube. The orifice is positioned between two hose ports coming off the tube which are connected to the DPFE sensor with special heat-resistant hoses. When the EGR Valve is open, a pressure differential is created across the orifice (intake manifold pressure vs. exhaust pressure). By design, this difference in pressure is measured by the DPFE sensor in terms of voltage. The DPFE voltage signal output to the PCM is directly proportional to the flow of exhaust gas entering the intake manifold.

OBDII Code P1400 Mercury - Differential Pressure Feedback Electronic Sensor Circuit Low Voltage - AutoCodes.com — P1400 Mercury Code - Differential Pressure Feedback Electronic Sensor Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P1400 Mercury?

Differential Pressure Feedback Electronic Sensor harness is open or shorted
Differential Pressure Feedback Electronic Sensor circuit poor electrical connection
Faulty Differential Pressure Feedback Electronic Sensor

How to Fix the DTC P1400 Mercury?

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

There is a factory service bulletin for the following Mercury models:

2000-2002 Mercury Sable
2001-2002 Mercury Cougar
2001-2002 Mercury Grand Marquis
2002-2003 Mercury Mountaineer
Mercury Factory Service Bulletin OBDII Code P1400 Code

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1400 Mercury 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 P1400 Mercury code?

Need more information on how to fix the P1400 Mercury code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1400 Mercury code diagnosed by a professional: Find a repair shop in your area

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 P1400 Mercury Code

1. What are the common symptoms of OBDII code P1400 on a Mercury vehicle?

The common symptoms of OBDII code P1400 on a Mercury vehicle may include rough idling, engine stalling, poor fuel efficiency, and the illumination of the Check Engine Light.

2. What are the possible causes of OBDII code P1400 on a Mercury vehicle?

The possible causes of OBDII code P1400 on a Mercury vehicle may include a faulty DPFE sensor, damaged wiring or connectors in the DPFE circuit, exhaust leaks, or issues with the EGR valve.

3. How can I diagnose OBDII code P1400 on my Mercury vehicle?

Diagnosing OBDII code P1400 on a Mercury vehicle typically involves using a scan tool to retrieve the trouble code, checking the DPFE sensor for proper operation, inspecting the wiring and connectors for damage, and testing the EGR system for functionality.

4. Can I continue driving my Mercury with OBDII code P1400?

It is not recommended to continue driving your Mercury with OBDII code P1400, as it can lead to engine performance issues and potential damage if left unresolved. It is best to address the issue promptly.

5. How can I repair OBDII code P1400 on my Mercury vehicle?

Repairing OBDII code P1400 on a Mercury vehicle may involve replacing the DPFE sensor, repairing or replacing damaged wiring or connectors, fixing any exhaust leaks, or cleaning or replacing the EGR valve.

6. Are there any DIY tips for fixing OBDII code P1400 on my Mercury?

Some DIY tips for fixing OBDII code P1400 on your Mercury include checking and cleaning the EGR valve, inspecting the DPFE sensor for debris, and ensuring all connections in the circuit are secure and free of corrosion.

7. How much does it cost to repair OBDII code P1400 on a Mercury vehicle?

The cost to repair OBDII code P1400 on a Mercury vehicle can vary depending on the specific cause of the issue and the labor rates in your area. Generally, it may range from $100 to $300 for parts and labor.

8. Can a mechanic help me fix OBDII code P1400 on my Mercury?

Yes, a qualified mechanic can help diagnose and repair OBDII code P1400 on your Mercury vehicle. They have the expertise and tools necessary to accurately identify the issue and perform the repairs needed.

9. Will resetting the Check Engine Light resolve OBDII code P1400 on my Mercury?

Simply resetting the Check Engine Light will not resolve OBDII code P1400 on your Mercury. The underlying issue causing the code needs to be diagnosed and fixed to prevent further problems.

10. How often does OBDII code P1400 occur in Mercury vehicles?

OBDII code P1400, related to the Differential Pressure Feedback Electronic Sensor Circuit Low Voltage, can occur in Mercury vehicles with EGR systems, particularly in models equipped with DPFE sensors.