AutoCodes – Chevrolet – B393B 2018 Chevrolet Silverado

B393B 2018 Chevrolet Silverado Code - Air Conditioning Compressor Valve Control Circuit

Quick Answer

This A/C system uses a conventional clutch to engage and mechanically turn the compressor and a variable displacement solenoid valve to alter the amount of displacement created by the turning of the compressor. Common causes include Faulty Air Conditioning Compressor, Air Conditioning Compressor harness is open or shorted, Air Conditioning Compressor 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: B393B 2018 Chevrolet Silverado indicates Air Conditioning Compressor Valve Control Circuit.
Common causes: Common causes include Faulty Air Conditioning Compressor, Air Conditioning Compressor harness is open or shorted, Air Conditioning Compressor 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 624

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 Jun 17, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B393B 2018 Chevrolet Silverado Description

This A/C system uses a conventional clutch to engage and mechanically turn the compressor and a variable displacement solenoid valve to alter the amount of displacement created by the turning of the compressor. The Heating, Ventilation, and Air Conditioning (HVAC) Control Module provides both switched battery voltage and a pulse width modulated ground to the variable displacement solenoid valve. When the A/C switch is pressed, the HVAC Control Module grounds the variable displacement solenoid using a Pulse Width Modulation (PWM) signal in order to determine the amount of compressor displacement. The performance of the A/C compressor is based on adjusted interior temperature and engine load. The Diagnostic Trouble Code (DTC) sets when a PWM greater than 10% is sent but no current is read back.

OBDII Code B393B 2018 Chevrolet Silverado - Air Conditioning Compressor Valve Control Circuit - AutoCodes.com — B393B 2018 Chevrolet Silverado Code - Air Conditioning Compressor Valve Control Circuit

What does this mean?

What are the Possible Causes of the DTC B393B 2018 Chevrolet Silverado?

Faulty Air Conditioning Compressor
Air Conditioning Compressor harness is open or shorted
Air Conditioning Compressor circuit poor electrical connection
Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module

How to Fix the DTC B393B 2018 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 B393B 2018 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 B393B 2018 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 B393B 2018 Chevrolet Silverado Code

1. What does the OBDII code B393B mean on a 2018 Chevrolet Silverado?

The B393B code indicates an issue with the Air Conditioning Compressor Valve Control Circuit, which may involve an electrical fault or malfunction in the system controlling the compressor valve.

2. What are common symptoms of the B393B code in a 2018 Chevrolet Silverado?

Common symptoms include the A/C not blowing cold air, inconsistent cooling performance, or the A/C compressor failing to engage properly.

3. What causes the B393B code to appear in a 2018 Chevrolet Silverado?

Possible causes include a faulty air conditioning compressor valve, damaged wiring or connectors in the control circuit, or a malfunctioning A/C control module.

4. Can I still drive my 2018 Chevrolet Silverado with the B393B code?

Yes, you can drive the vehicle, but the air conditioning may not function correctly, leading to discomfort in hot weather.

5. How do you diagnose the B393B OBDII code in a 2018 Chevrolet Silverado?

Diagnosis involves using a scan tool to confirm the code, inspecting the wiring and connectors for damage or corrosion, and testing the compressor valve and circuit for proper operation.

6. What repairs are needed to fix the B393B code in a 2018 Chevrolet Silverado?

Repairs may include replacing the air conditioning compressor valve, repairing or replacing damaged wiring or connectors, or reprogramming the A/C control module if necessary.

7. How much does it cost to repair the B393B code in a 2018 Chevrolet Silverado?

Repair costs can vary but typically range from $150 to $500, depending on whether the issue is with the valve, wiring, or control module.

8. Can a faulty A/C compressor cause the B393B code?

Yes, a faulty or failing A/C compressor or its valve can trigger the B393B code due to improper circuit operation.

9. How can I prevent the B393B code from occurring again?

Regularly inspect and maintain the A/C system, including checking wiring and connectors for damage and ensuring the compressor is functioning properly.

10. Do I need to clear the B393B code after repairs?

Yes, after completing repairs, use a scan tool to clear the code and ensure the issue does not reappear during a test drive.