AutoCodes – Chevrolet – P0402 2015 Chevrolet Silverado

P0402 2015 Chevrolet Silverado Code - Exhaust Gas Recirculation Flow Excessive

Quick Answer

The Exhaust Gas Recirculation (EGR) valve is controlled by the Engine Control Module (ECM). Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, EGR solenoid valve harness is open or shorted, EGR solenoid valve circuit poor electrical connection. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

What it means: P0402 2015 Chevrolet Silverado indicates Exhaust Gas Recirculation Flow Excessive.
Common causes: Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, EGR solenoid valve harness is open or shorted, EGR solenoid valve circuit poor electrical connection.
Severity: Moderate - service should be scheduled soon.
Can I drive?: The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

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Code Popularity 300

How popular is this code, among other codes? Low

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 19, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0402 2015 Chevrolet Silverado Description

The Exhaust Gas Recirculation (EGR) valve is controlled by the Engine Control Module (ECM). The ECM controls the EGR valve by supplying a 12-volt pulse width modulated signal to the EGR Valve low control circuit and 12 volts to the high control circuit. The ECM monitors the EGR flow performance when the EGR is active by comparing the desired Mass Air Flow (MAF) to the actual MAF. If the difference between the desired MAF and the actual MAF is less than or greater than a calibrated threshold level the amount of detected EGR flow is out of range. The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the difference between the desired mass air flow and the actual mass air flow is less than a calibrated value for greater than 12.5 s.

OBDII Code P0402 2015 Chevrolet Silverado - Exhaust Gas Recirculation Flow Excessive - AutoCodes.com — P0402 2015 Chevrolet Silverado Code - Exhaust Gas Recirculation Flow Excessive

What does this mean?

What are the Possible Causes of the DTC P0402 2015 Chevrolet Silverado?

Faulty Exhaust Gas Recirculation (EGR) Valve
EGR solenoid valve harness is open or shorted
EGR solenoid valve circuit poor electrical connection

How to Fix the DTC P0402 2015 Chevrolet Silverado?

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 P0402 2015 Chevrolet Silverado 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 P0402 2015 Chevrolet Silverado 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 P0402 2015 Chevrolet Silverado Code

1. What are the common symptoms of an OBDII code P0402 in a 2015 Chevrolet Silverado?

- Common symptoms include rough idle, decreased fuel efficiency, engine hesitation, and potentially the illumination of the check engine light.

2. What can cause the OBDII code P0402 in a 2015 Chevrolet Silverado?

- The code P0402 typically indicates excessive exhaust gas recirculation (EGR) flow, which can be caused by a faulty EGR valve, clogged EGR passages, or a malfunctioning EGR system.

3. How can I diagnose the OBDII code P0402 in my 2015 Chevrolet Silverado?

- Diagnosis involves checking the EGR valve for proper operation, inspecting EGR system components for blockages, and using a scan tool to monitor EGR system data.

4. Can a dirty or clogged EGR valve trigger the OBDII code P0402 in a 2015 Chevrolet Silverado?

- Yes, a dirty or clogged EGR valve can disrupt the proper flow of exhaust gas recirculation, leading to the triggering of the code P0402.

5. What are some repair tips for resolving the OBDII code P0402 in a 2015 Chevrolet Silverado?

- Repair tips include cleaning or replacing the EGR valve, clearing any blockages in the EGR system, and ensuring proper electrical connections in the EGR system.

6. Is it safe to continue driving a 2015 Chevrolet Silverado with an OBDII code P0402?

- It is not recommended to drive with an unresolved P0402 code as it can lead to reduced engine performance and potentially cause further damage to the vehicle over time.

7. Can a malfunctioning EGR system affect the emissions of a 2015 Chevrolet Silverado?

- Yes, a malfunctioning EGR system can contribute to increased emissions of nitrogen oxides (NOx) in the vehicle's exhaust, impacting its environmental performance.

8. How much does it typically cost to repair the OBDII code P0402 in a 2015 Chevrolet Silverado?

- The cost of repairs can vary depending on the exact cause of the issue, but it may range from a few hundred dollars for simple fixes like cleaning the EGR valve to over a thousand dollars for more extensive repairs.

9. Are there any preventative maintenance steps I can take to avoid the OBDII code P0402 in my 2015 Chevrolet Silverado?

- Regularly servicing and inspecting the EGR system components, using high-quality fuel, and driving at moderate speeds can help prevent issues that may trigger the P0402 code.

10. Will resetting the check engine light clear the OBDII code P0402 in a 2015 Chevrolet Silverado?

- Resetting the check engine light may temporarily turn it off, but if the underlying issue causing the P0402 code is not addressed, the light is likely to come back on as the problem persists.