AutoCodes – Generic – B2639

B2639 Code - Driver DEF Door Fail

Quick Answer

The Air Condition (A/C) Automatic Amplifier monitors the Front Mode Door Motor position. Common causes include Faulty Front Mode Door Motor, Front Mode Door Motor harness is open or shorted, Front Mode Door Motor 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: B2639 indicates Driver DEF Door Fail.
Common causes: Common causes include Faulty Front Mode Door Motor, Front Mode Door Motor harness is open or shorted, Front Mode Door Motor 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 3,736

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 Jan 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B2639 Description

The Air Condition (A/C) Automatic Amplifier monitors the Front Mode Door Motor position. The A/C Automatic Amplifier sets the Diagnostic Trouble Code (DTC) when the malfunctioning door position is detected at DEF position.

OBDII Code B2639 - Driver DEF Door Fail - AutoCodes.com — B2639 Code - Driver DEF Door Fail

What does this mean?

What are the Possible Causes of the DTC B2639?

Faulty Front Mode Door Motor
Front Mode Door Motor harness is open or shorted
Front Mode Door Motor circuit poor electrical connection
Front Mode Door Motor control linkage installation condition
Faulty Air Condition (A/C) Automatic Amplifier

How to Fix the DTC B2639?

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 B2639 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 B2639 code?

Need more information on how to fix the B2639 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B2639 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B2639 Infiniti — Driver DEF Door Fail
B2639 Nissan — Driver DEF Door Fail

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 B2639 Code

1. What are the common symptoms of OBDII code B2639 (Driver DEF Door Fail)?

- The common symptoms include illuminated check engine light, DEF system warnings, and potential issues with the diesel exhaust fluid door.

2. What are the possible causes of OBDII code B2639?

- The code B2639 can be triggered by a faulty DEF door actuator, damaged wiring, or a malfunction in the DEF door assembly.

3. How can I diagnose the OBDII code B2639 related to the Driver DEF Door Fail?

- A thorough inspection of the DEF door components, wiring, and actuator is necessary to diagnose the issue accurately. Using a diagnostic scanner can help pinpoint the problem.

4. What are some DIY repair tips for fixing OBDII code B2639?

- DIY repair tips may include checking and repairing damaged wiring, replacing the DEF door actuator, or cleaning and lubricating the DEF door mechanism.

5. Can OBDII code B2639 pose any serious issues if left unaddressed?

- Ignoring OBDII code B2639 may lead to improper DEF fluid distribution, potential DEF system malfunctions, and increased emissions.

6. How much does it typically cost to repair OBDII code B2639 (Driver DEF Door Fail)?

- The cost of repairing OBDII code B2639 can vary based on the specific cause of the issue, but it may range from $100 to $300 for parts and labor.

7. Is it safe to continue driving with OBDII code B2639 present?

- It is not recommended to drive with OBDII code B2639 present, as it can affect the proper functioning of the DEF system and potentially lead to more serious issues.

8. Can a simple reset of the OBDII system clear the B2639 code?

- While resetting the OBDII system may temporarily clear the B2639 code, it is crucial to address the underlying issue causing the code to prevent it from reoccurring.

9. Are there any recalls or technical service bulletins related to OBDII code B2639?

- It is advisable to check with the vehicle manufacturer or authorized dealerships for any recalls or technical service bulletins related to OBDII code B2639 to see if there are any known solutions or remedies.

10. How can regular maintenance help prevent OBDII code B2639 from occurring?

- Regular inspection and maintenance of the DEF system components, including the DEF door and actuator, can help prevent issues that may trigger OBDII code B2639.