AutoCodes – GMC – P1008 2016 GMC Sierra

P1008 2016 GMC Sierra Code - Engine Coolant Bypass Valve Command 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 Engine Coolant Bypass Valve, Engine Coolant Bypass Valve harness is open or shorted, Engine Coolant Bypass Valve 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: P1008 2016 GMC Sierra indicates Engine Coolant Bypass Valve Command Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Engine Coolant Bypass Valve, Engine Coolant Bypass Valve harness is open or shorted, Engine Coolant Bypass Valve 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 187

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 Aug 18, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1008 2016 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 Engine Coolant Bypass Valve Command Signal Message Counter is Incorrect.

OBDII Code P1008 2016 GMC Sierra - Engine Coolant Bypass Valve Command Signal Message Counter Incorrect - AutoCodes.com — P1008 2016 GMC Sierra Code - Engine Coolant Bypass Valve Command Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P1008 2016 GMC Sierra?

Faulty Engine Coolant Bypass Valve
Engine Coolant Bypass Valve harness is open or shorted
Engine Coolant Bypass Valve circuit poor electrical connection

How to Fix the DTC P1008 2016 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 P1008 2016 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 P1008 2016 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 P1008 2016 GMC Sierra Code

1. What does the OBDII code P1008 mean on a 2016 GMC Sierra?

The code P1008 indicates an issue with the engine coolant bypass valve command signal, where the message counter is incorrect or inconsistent.

2. What are the common symptoms of the P1008 code?

Symptoms may include an illuminated check engine light, potential overheating issues, poor heater performance, or reduced engine efficiency.

3. What causes the P1008 code on a 2016 GMC Sierra?

Common causes include a faulty engine coolant bypass valve, wiring or connector issues, a malfunctioning powertrain control module (PCM), or corrupted communication signals.

4. Can the P1008 code cause engine damage?

If left unresolved, the P1008 code can lead to improper coolant flow, potentially causing overheating and damage to the engine.

5. How do you diagnose the P1008 code?

A technician will typically use a scan tool to check for related codes, inspect the coolant bypass valve and its wiring, and test the signal communication between the valve and the PCM.

6. How is the P1008 code fixed?

Repairs may include replacing the engine coolant bypass valve, repairing damaged wiring or connectors, or reprogramming or replacing the PCM if necessary.

7. Can I drive with the P1008 code on my 2016 GMC Sierra?

While the vehicle may still be drivable, itâ€™s not recommended as the issue can lead to overheating and further engine damage.

8. How much does it cost to repair the P1008 code?

Repair costs vary depending on the cause but may range from $150 to $500, including parts and labor.

9. Does the P1008 code require a software update?

In some cases, a PCM software update may be necessary to resolve communication issues causing the P1008 code.

10. Can a low coolant level trigger the P1008 code?

While low coolant levels are not a direct cause, they can contribute to overheating issues that may compound the problem with the coolant bypass valve system.