AutoCodes – GMC – P1103 2018 GMC Sierra

P1103 2018 GMC Sierra Code - Water In Fuel Signal Message Counter Incorrect

Quick Answer

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Common causes include Faulty Water In Fuel Sensor, Water In Fuel Sensor harness is open or shorted, Water In Fuel Sensor 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: P1103 2018 GMC Sierra indicates Water In Fuel Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Water In Fuel Sensor, Water In Fuel Sensor harness is open or shorted, Water In Fuel Sensor 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 324

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 26, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1103 2018 GMC Sierra Description

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Operating information and commands are exchanged among the control modules. Each module on the serial data circuit maintains a transmit error counter and a receive error counter. The counter values increase with detected errors and decrease with error-free messages. The Diagnostic Trouble Code (DTC) will be set when the Water In Fuel Signal Message Counter is Incorrect.

OBDII Code P1103 2018 GMC Sierra - Water In Fuel Signal Message Counter Incorrect - AutoCodes.com — P1103 2018 GMC Sierra Code - Water In Fuel Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P1103 2018 GMC Sierra?

Faulty Water In Fuel Sensor
Water In Fuel Sensor harness is open or shorted
Water In Fuel Sensor circuit poor electrical connection

How to Fix the DTC P1103 2018 GMC Sierra?

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 P1103 2018 GMC Sierra 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 P1103 2018 GMC Sierra code?

Need more information on how to fix the P1103 2018 GMC Sierra code? Get Access to Factory Service Manuals

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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 P1103 2018 GMC Sierra Code

1. What does the OBDII code P1103 mean on a 2018 GMC Sierra?

P1103 indicates an issue with the water-in-fuel signal message counter being incorrect, which suggests a problem with the fuel system's ability to detect water contamination.

2. What are the common symptoms of code P1103?

Symptoms may include a "Water in Fuel" warning message, reduced engine performance, rough idling, or difficulty starting the engine.

3. What causes the P1103 code to appear?

Common causes include a faulty water-in-fuel sensor, contaminated fuel, wiring or connector issues, or a malfunction in the fuel filter assembly.

4. Can driving with code P1103 damage my 2018 GMC Sierra?

Yes, driving with water contamination in the fuel can damage fuel injectors, the fuel pump, and other engine components if not addressed.

5. How do I diagnose code P1103?

Start by inspecting the water-in-fuel sensor and its wiring for damage or corrosion. Check the fuel system for water contamination and verify the sensor's functionality with a scan tool.

6. What repairs can fix code P1103?

Repairs may include replacing the water-in-fuel sensor, draining and refilling the fuel tank, cleaning the fuel system, or repairing damaged wiring or connectors.

7. How can I prevent code P1103 from recurring?

Use high-quality fuel, regularly replace the fuel filter, and inspect the fuel system for water contamination during routine maintenance.

8. Is the water-in-fuel sensor expensive to replace?

The cost of replacing the water-in-fuel sensor varies, but it typically ranges from $50 to $200, depending on parts and labor.

9. Can I clear the P1103 code without fixing the issue?

You can clear the code temporarily with a scan tool, but it will likely return if the underlying problem isn't resolved.

10. Do I need professional help to fix code P1103?

If you're unfamiliar with diagnosing and repairing fuel system issues, itâ€™s best to consult a professional mechanic to ensure the problem is properly addressed.