P1008 2018 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 2018 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.
Code P1008 2018 GMC Sierra Description
What are the Possible Causes of the DTC P1008 2018 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 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 P1008 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.
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Frequently Asked Questions about P1008 2018 GMC Sierra Code
1. What does OBDII code P1008 mean on a 2018 GMC Sierra?
Code P1008 indicates that the Engine Coolant Bypass Valve Command Signal Message Counter was found to be incorrect, meaning there's a communication or performance issue with the coolant bypass valve.
2. What are the common symptoms of code P1008 in a 2018 GMC Sierra?
Symptoms may include an illuminated check engine light, engine overheating or running cooler than normal, poor cabin heating, and fluctuating temperature gauge readings.
3. What causes code P1008 on a 2018 GMC Sierra?
Common causes include a faulty coolant bypass valve, wiring issues, a poor electrical connection, or a malfunction in the engine control module (ECM).
4. Can I drive my 2018 GMC Sierra with code P1008?
Driving with this code is not recommended, as improper coolant flow can lead to engine overheating and potential damage if not addressed promptly.
5. How do you diagnose code P1008 on a 2018 GMC Sierra?
A technician will use a scan tool to confirm the code, inspect the coolant bypass valve and its wiring, check for proper electrical signals, and verify the ECM is functioning correctly.
6. How do you fix code P1008 on a 2018 GMC Sierra?
Repairs may include replacing the coolant bypass valve, repairing damaged wiring or connectors, and, in rare cases, reprogramming or replacing the ECM.
7. Is code P1008 a common issue in the 2018 GMC Sierra?
While not extremely common, this code can occur due to wear and tear on the coolant bypass valve or electrical problems related to the system.
8. How much does it cost to repair code P1008 on a 2018 GMC Sierra?
Repair costs vary but typically range between $150 and $500, depending on whether the issue is with the valve, wiring, or ECM.
9. Can a faulty thermostat cause code P1008 on a 2018 GMC Sierra?
While a faulty thermostat is not a direct cause, it may exacerbate temperature regulation issues, potentially triggering related codes.
10. How can I prevent code P1008 on my 2018 GMC Sierra?
Regular maintenance of the cooling system, including inspecting coolant bypass valve components and wiring for damage, can help prevent this issue.
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