AutoCodes – GMC – P1591 2018 GMC Sierra

P1591 2018 GMC Sierra Code - Body Control Module Engine Speed Request 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 Body Control Module, Body Control Module harness is open or shorted, Body Control Module 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: P1591 2018 GMC Sierra indicates Body Control Module Engine Speed Request Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Body Control Module, Body Control Module harness is open or shorted, Body Control Module 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 166

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 28, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1591 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 Body Control Module Engine Speed Request Signal Message Counter is Incorrect.

OBDII Code P1591 2018 GMC Sierra - Body Control Module Engine Speed Request Signal Message Counter Incorrect - AutoCodes.com — P1591 2018 GMC Sierra Code - Body Control Module Engine Speed Request Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P1591 2018 GMC Sierra?

Faulty Body Control Module
Body Control Module harness is open or shorted
Body Control Module circuit poor electrical connection

How to Fix the DTC P1591 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 P1591 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 P1591 2018 GMC Sierra 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 P1591 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P1591 in a 2018 GMC Sierra?

- Common symptoms include engine stalling, rough idling, decreased fuel efficiency, and issues with the vehicle's electrical systems.

2. What does the OBDII code P1591 "Body Control Module Engine Speed Request Signal Message Counter Incorrect" mean for a 2018 GMC Sierra?

- This code indicates a communication error between the body control module and the engine control module related to the engine speed request signal counter.

3. What are the possible causes of OBDII code P1591 in a 2018 GMC Sierra?

- Potential causes include faulty wiring or connectors, a malfunctioning body control module, issues with the engine control module, or a software glitch.

4. How can I diagnose the OBDII code P1591 in my 2018 GMC Sierra?

- Diagnosing this code may involve checking the wiring and connectors for any damage, testing the body control module and engine control module, and using a diagnostic scanner to read live data.

5. How serious is the OBDII code P1591 in a 2018 GMC Sierra?

- While the vehicle may still be operable with this code, ignoring it can lead to further electrical or engine performance problems over time.

6. Can I drive my 2018 GMC Sierra with the OBDII code P1591?

- It is generally recommended to address the underlying issue causing the code before driving the vehicle extensively to prevent potential damage or safety hazards.

7. How do I reset the OBDII code P1591 in my 2018 GMC Sierra?

- Clearing the code can be done using an OBDII scanner or by disconnecting the vehicle's battery for a few minutes. However, the code may return if the root problem is not fixed.

8. Can I repair the OBDII code P1591 in my 2018 GMC Sierra myself?

- Depending on your skill level and access to tools, you may be able to address this code yourself by checking and repairing the wiring, connectors, or modules involved.

9. Will the OBDII code P1591 affect my vehicle's emissions test in a 2018 GMC Sierra?

- Yes, unresolved OBDII trouble codes like P1591 can cause a vehicle to fail an emissions test due to the impact on engine performance and emissions control systems.

10. How much does it cost to fix the OBDII code P1591 in a 2018 GMC Sierra?

- The cost of repairs can vary widely depending on the specific cause of the code, ranging from a simple wiring fix to potentially replacing the body control module or engine control module.