AutoCodes – GMC – P1591 GMC

P1591 GMC 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 GMC 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 407

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

What does this mean?

What are the Possible Causes of the DTC P1591 GMC?

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 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 P1591 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 P1591 GMC code?

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Need Help with the Code?

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Information for Specific GMC Models

P1591 2014 GMC Sierra — Body Control Module Engine Speed Request Signal Message Counter Incorrect
P1591 2015 GMC Sierra — Body Control Module Engine Speed Request Signal Message Counter Incorrect
P1591 2016 GMC Sierra — Body Control Module Engine Speed Request Signal Message Counter Incorrect
P1591 2017 GMC Sierra — Body Control Module Engine Speed Request Signal Message Counter Incorrect
P1591 2018 GMC Sierra — Body Control Module Engine Speed Request Signal Message Counter Incorrect

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 GMC Code

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

- Common symptoms include issues with starting the vehicle, engine stalling, poor engine performance, and illuminated warning lights on the dashboard.

2. What does the OBDII code P1591 indicate in a GMC vehicle?

- This code indicates that the Body Control Module (BCM) has detected an incorrect engine speed request signal message counter.

3. What are some possible causes of OBDII code P1591 in a GMC vehicle?

- Possible causes include a faulty BCM, wiring or connection issues between the BCM and the engine control module (ECM), a malfunctioning ECM, or a software-related issue.

4. How can I diagnose the cause of OBDII code P1591 in my GMC vehicle?

- A thorough inspection of the BCM, ECM, and related wiring is recommended. Using a diagnostic scanner to retrieve freeze frame data can also help pinpoint the issue.

5. Can I still drive my GMC vehicle with OBDII code P1591 present?

- It is not recommended to drive the vehicle with this code present, as it can lead to further engine performance issues or potential stalling while driving.

6. How can I repair OBDII code P1591 in my GMC vehicle?

- Repair options may include repairing or replacing faulty wiring, replacing the BCM or ECM if necessary, and performing any software updates recommended by the manufacturer.

7. Is it possible to reset OBDII code P1591 in a GMC vehicle using a diagnostic tool?

- Yes, a diagnostic tool can be used to clear the code after the underlying issue has been diagnosed and repaired.

8. Are there any DIY tips for troubleshooting OBDII code P1591 in a GMC vehicle?

- DIY tips may include checking for loose or damaged wiring connections, ensuring proper grounding of the BCM and ECM, and verifying the integrity of related fuses.

9. How long does it typically take to repair OBDII code P1591 in a GMC vehicle?

- The repair time can vary depending on the exact cause of the code, but it may take anywhere from a few hours to a full day to diagnose and repair the issue.

10. Can OBDII code P1591 in a GMC vehicle cause any long-term damage if left unaddressed?

- Ignoring this code can potentially lead to further damage to the engine or other components, so it is advisable to address it promptly to prevent any long-term issues.