AutoCodesGMC – P1400 2015 GMC Sierra

P1400 2015 GMC Sierra Code - Cold Start Emission Reduction Control System

Quick Answer

The catalytic converter must be warmed to efficiently reduce emissions. Common causes include Dirty Throttle Body, Dirty Air Filter, Dirty Mass Air Flow (MAF) Sensor. 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
P1400 2015 GMC Sierra indicates Cold Start Emission Reduction Control System.
Common causes
Common causes include Dirty Throttle Body, Dirty Air Filter, Dirty Mass Air Flow (MAF) Sensor.
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 272
How popular is this code, among other codes? Low
Table of contents Created and updated by William Orellana on Aug 13, 2022
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Code P1400 2015 GMC Sierra Description

The catalytic converter must be warmed to efficiently reduce emissions. The cold start strategy is to reduce the amount of time it takes to warm the catalytic converter. During a cold start, the engine idle speed is elevated, and spark timing is retarded to allow the catalyst to warm quickly. This diagnostic monitors the following to build an exhaust energy model: Engine speed, Spark advance, Throttle position, Engine airflow, Engine coolant temperature, Engine runtime, Park/neutral position, Vehicle speed. The actual model is then compared to the expected exhaust energy model. The Diagnostic Trouble Code (DTC) will set when the actual exhaust energy model does not match the expected exhaust energy model.
OBDII Code P1400 2015 GMC Sierra - Cold Start Emission Reduction Control System - AutoCodes.com
P1400 2015 GMC Sierra Code - Cold Start Emission Reduction Control System

What are the Possible Causes of the DTC P1400 2015 GMC Sierra?

  • Dirty Throttle Body
  • Dirty Air Filter
  • Dirty Mass Air Flow (MAF) Sensor
  • Intake manifold leak
  • Exhaust leak
  • Damaged, restricted, modified or enhanced exhaust system

How to Fix the DTC P1400 2015 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 P1400 2015 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 P1400 2015 GMC Sierra code?

Need more information on how to fix the P1400 2015 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the 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 P1400 2015 GMC Sierra Code

1. What does the OBDII code P1400 mean on a 2015 GMC Sierra?

P1400 indicates an issue with the Cold Start Emission Reduction Control System, which is designed to reduce emissions during cold engine starts.

2. What are the common symptoms of the P1400 code in a 2015 GMC Sierra?

Symptoms may include the check engine light turning on, reduced fuel efficiency, rough idling during cold starts, and increased exhaust emissions.

3. What causes the P1400 code in a 2015 GMC Sierra?

Common causes include a faulty cold start emission reduction valve, wiring issues, a malfunctioning PCM (Powertrain Control Module), or carbon buildup in the system.

4. Can I drive my 2015 GMC Sierra with the P1400 code active?

While the vehicle may still be drivable, driving with this code can lead to increased emissions and potential engine performance issues if not addressed.

5. How do I diagnose the P1400 code on a 2015 GMC Sierra?

Diagnosis involves using an OBDII scanner, inspecting the cold start emission reduction valve, checking for damaged wiring or connectors, and testing the functionality of the PCM.

6. How is the P1400 code typically fixed on a 2015 GMC Sierra?

Repairs may include cleaning or replacing the cold start emission reduction valve, repairing damaged wiring, or reprogramming or replacing the PCM if necessary.

7. How much does it cost to fix the P1400 code on a 2015 GMC Sierra?

Repair costs can vary, but replacing the cold start emission reduction valve typically ranges from $150 to $400, depending on labor and parts.

8. Can a dirty air filter trigger the P1400 code on a 2015 GMC Sierra?

While unlikely, a restricted air filter can affect overall engine performance and emissions, so it’s worth inspecting as part of the diagnostic process.

9. Is the P1400 code related to the EGR system on a 2015 GMC Sierra?

No, the P1400 code specifically pertains to the Cold Start Emission Reduction Control System and not the Exhaust Gas Recirculation (EGR) system.

10. Will clearing the P1400 code solve the problem on a 2015 GMC Sierra?

Clearing the code will turn off the check engine light temporarily, but the underlying issue must be repaired to prevent the code from returning.

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