AutoCodes – Generic – B3387

B3387 Code - Right Front Window Up Switch Circuit Low

Quick Answer

The window switch or window switch circuits that generate this Diagnostic Trouble Code (DTC) are built-in parts of the Driver Door Switch Assembly (DDSA). Common causes include Faulty Driver Door Switch Assembly (DDSA), Driver Door Switch Assembly (DDSA) harness is open or shorted, Driver Door Switch Assembly (DDSA) 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: B3387 indicates Right Front Window Up Switch Circuit Low.
Common causes: Common causes include Faulty Driver Door Switch Assembly (DDSA), Driver Door Switch Assembly (DDSA) harness is open or shorted, Driver Door Switch Assembly (DDSA) 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 596

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 Mar 06, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3387 Description

The window switch or window switch circuits that generate this Diagnostic Trouble Code (DTC) are built-in parts of the Driver Door Switch Assembly (DDSA). There are no external circuits. The DDSA internally supplies power and ground to the contacts of each of the integral window switches. When one of the switches is operated, the switch contacts close, providing the DDSA with a specific window switch signal. The DDSA processes this signal, assigns a digital message to it, and sends the message to the appropriate Driver Door Module (DDM), Passenger Front Door Module (PDM), Left Rear Door Module (LRDM), or Right Rear Door Module (RRDM), via the class 2 serial data circuit. The door module, upon receiving the message, examines other relevant information available on the class 2 serial data line in order to determine if conditions are correct for window operation to occur. If conditions are correct, the door module applies power and ground to the associated window motor and circuits in order to move the window. If the DDSA determines that one of its built in window switches is closed for more than 15 continuous seconds, it sets the DTC.

OBDII Code B3387 - Right Front Window Up Switch Circuit Low - AutoCodes.com — B3387 Code - Right Front Window Up Switch Circuit Low

What does this mean?

What are the Possible Causes of the DTC B3387?

Faulty Driver Door Switch Assembly (DDSA)
Driver Door Switch Assembly (DDSA) harness is open or shorted
Driver Door Switch Assembly (DDSA) circuit poor electrical connection
Faulty Passenger Front Door Module (PDM)
Faulty Driver Door Module (DDM)

How to Fix the DTC B3387?

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 B3387 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 B3387 code?

Need more information on how to fix the B3387 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3387 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B3387 Buick — Right Front Window Up Switch Circuit Low
B3387 Cadillac — Right Front Window Up Switch Circuit Low
B3387 Chevrolet — Right Front Window Up Switch Circuit Low
B3387 GMC — Right Front Window Up Switch Circuit Low

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 B3387 Code

1. What does the OBDII code B3387 mean?

The B3387 code indicates a low voltage or malfunction in the right front window up switch circuit, suggesting an issue with the electrical pathway controlling the window's upward movement.

2. What are the common symptoms of the B3387 code?

Symptoms may include the right front window not rolling up, intermittent functionality, or no response from the window switch.

3. What causes the B3387 code to appear?

Common causes include a faulty window switch, damaged wiring or connectors in the circuit, or a malfunctioning window motor.

4. How is the B3387 code diagnosed?

A technician will inspect the window switch, check the wiring and connectors for damage or corrosion, and test the circuit's voltage to identify the fault.

5. Can I still drive with the B3387 code active?

Yes, your vehicle is still drivable, but the right front window may not function properly, which could be inconvenient or a security risk.

6. How do you fix the B3387 code?

Repairs may involve replacing the window switch, repairing or replacing damaged wiring, or addressing issues with the window motor or control module.

7. How much does it cost to repair the B3387 code?

Repair costs vary but typically range from $100 to $300, depending on whether the issue is a faulty switch, damaged wiring, or another component.

8. Can I fix the B3387 code myself?

If you're experienced with electrical systems, you can inspect and replace the window switch or repair damaged wiring. However, a professional diagnosis is recommended for more complex issues.

9. Will clearing the B3387 code with a scan tool fix the problem?

Clearing the code may temporarily remove it, but the underlying issue must be resolved to prevent the code from returning.

10. What tools are needed to troubleshoot the B3387 code?

Common tools include a multimeter, wiring diagrams, and possibly a scan tool to monitor live data and confirm proper circuit operation.

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