AutoCodes – GMC – P16E4 GMC

P16E4 GMC Code - Sensor Communication Circuit 3 Low Voltage

Quick Answer

The Engine Control Module (ECM) uses the Fuel Rail Pressure (FRP) sensor to constantly adjust the high-pressure fuel pump's feed rate so that the ideal pressure is permanently maintained in the high-pressure section (between the high-pressure fuel pump and the injectors) by means of closed-loop control. Common causes include Low or no fuel, Faulty Fuel Rail Pressure (FRP) Sensor, Fuel Rail Pressure harness is open or shorted. 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: P16E4 GMC indicates Sensor Communication Circuit 3 Low Voltage.
Common causes: Common causes include Low or no fuel, Faulty Fuel Rail Pressure (FRP) Sensor, Fuel Rail Pressure harness is open or shorted.
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 5,316

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 30, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P16E4 GMC Description

The Engine Control Module (ECM) uses the Fuel Rail Pressure (FRP) sensor to constantly adjust the high-pressure fuel pump's feed rate so that the ideal pressure is permanently maintained in the high-pressure section (between the high-pressure fuel pump and the injectors) by means of closed-loop control. The fuel rail pressure sensor transmits fuel pressure and temperature information via serial data to the ECM. When the fuel pressure is high, the signal voltage is high. When the fuel pressure is low, the signal voltage is low. The ECM controls the fuel pressure regulator, which regulates high-pressure fuel that goes to the fuel injector rails and the injectors. The Diagnostic Trouble Code (DTC) will be set if the Fuel Rail Pressure Sensor Signal is less than a predefined threshold for greater than 2.6 s.

OBDII Code P16E4 GMC - Sensor Communication Circuit 3 Low Voltage - AutoCodes.com — P16E4 GMC Code - Sensor Communication Circuit 3 Low Voltage

What does this mean?

What are the Possible Causes of the DTC P16E4 GMC?

Low or no fuel
Faulty Fuel Rail Pressure (FRP) Sensor
Fuel Rail Pressure harness is open or shorted
Fuel Rail Pressure circuit poor electrical connection
Faulty Fuel Pump

How to Fix the DTC P16E4 GMC?

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 P16E4 GMC 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 P16E4 GMC code?

Need more information on how to fix the P16E4 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P16E4 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

P16E4 2014 GMC Sierra — Sensor Communication Circuit 3 Low Voltage
P16E4 2015 GMC Sierra — Sensor Communication Circuit 3 Low Voltage
P16E4 2016 GMC Sierra — Sensor Communication Circuit 3 Low Voltage
P16E4 2017 GMC Sierra — Sensor Communication Circuit 3 Low Voltage
P16E4 2018 GMC Sierra — Sensor Communication Circuit 3 Low Voltage

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 P16E4 GMC Code

1. What does the OBDII code P16E4 mean on a GMC vehicle?

P16E4 indicates a problem with Sensor Communication Circuit 3, specifically a low voltage issue, which may affect communication between the sensor and the vehicle's control module.

2. What are the common symptoms of code P16E4 in GMC vehicles?

Symptoms may include illuminated check engine light, poor engine performance, erratic sensor readings, or difficulty starting the vehicle.

3. What causes the P16E4 code to appear on a GMC?

Common causes include a faulty sensor, damaged wiring, poor electrical connections, or a malfunctioning control module.

4. Can I drive my GMC with a P16E4 code?

It is not recommended to drive with this code active, as it may lead to reduced engine performance or further damage to the vehicle.

5. How do you diagnose the P16E4 code on a GMC?

Diagnosis involves using an OBDII scanner to confirm the code, inspecting wiring and connections for damage, and testing the sensor and control module voltages.

6. What repairs are typically needed for a P16E4 code?

Common repairs include replacing the faulty sensor, repairing or replacing damaged wiring, or reprogramming or replacing the control module if necessary.

7. How much does it cost to fix a P16E4 code on a GMC?

Repair costs vary depending on the exact issue but typically range from $100 to $500, including diagnostics, parts, and labor.

8. Can a low battery cause the P16E4 code?

Yes, a weak or low battery can potentially cause voltage issues, leading to communication circuit errors like P16E4.

9. How can I prevent the P16E4 code from occurring again?

Regular maintenance, including inspecting wiring and keeping electrical components in good condition, can help prevent this code from reoccurring.

10. Is a P16E4 code specific to GMC vehicles?

While the code may appear on other makes, its description and troubleshooting steps in GMC vehicles are specific to their system design. Always refer to the GMC service manual for accurate information.