AutoCodes – Generic – B2794

B2794 Code - Unmatched Encryption Code

Quick Answer

The Diagnostic Trouble Code (DTC) B2794 is stored when a key with an incomplete key ID code is inserted into the ignition key cylinder. Common causes include Faulty Key, Faulty Transponder Key Coil, Faulty Transponder Key ECU Assembly. 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: B2794 indicates Unmatched Encryption Code.
Common causes: Common causes include Faulty Key, Faulty Transponder Key Coil, Faulty Transponder Key ECU Assembly.
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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 2,292

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 16, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B2794 Description

The Diagnostic Trouble Code (DTC) B2794 is stored when a key with an incomplete key ID code is inserted into the ignition key cylinder.

OBDII Code B2794 - Unmatched Encryption Code - AutoCodes.com — B2794 Code - Unmatched Encryption Code

What does this mean?

What are the Possible Causes of the DTC B2794?

Faulty Key
Faulty Transponder Key Coil
Faulty Transponder Key ECU Assembly

How to Fix the DTC B2794?

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 B2794 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 B2794 code?

Need more information on how to fix the B2794 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B2794 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B2794 Lexus — Unmatched Encryption Code
B2794 Scion — Unmatched Encryption Code
B2794 Toyota — Unmatched Encryption Code

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 B2794 Code

1. What does OBDII code B2794 "Unmatched Encryption Code" mean?

- This code indicates a communication error between the key and the immobilizer system in the vehicle.

2. What are the common symptoms of OBDII code B2794?

- Common symptoms include the engine not starting, the security light flashing on the dashboard, and the key not being recognized by the vehicle's immobilizer system.

3. What are the possible causes of OBDII code B2794?

- Possible causes of this code include a faulty key fob, a malfunctioning immobilizer system, or a communication error between the key and the vehicle's security system.

4. How can I diagnose OBDII code B2794?

- Diagnosing this code typically involves using a professional OBDII scanner to retrieve the specific error code and then performing further testing to pinpoint the exact cause of the communication issue.

5. Can I repair OBDII code B2794 on my own?

- Repairing this code may require specialized knowledge and tools, so it is recommended to consult with a qualified automotive technician to properly diagnose and fix the issue.

6. Is it safe to continue driving with OBDII code B2794 present?

- It is not advisable to continue driving with this code active, as it may lead to starting issues or potential immobilization of the vehicle.

7. Are there any DIY tips to troubleshoot OBDII code B2794?

- DIY tips may include checking the key fob battery, ensuring the key is properly programmed, and inspecting the immobilizer system for any visible damage or loose connections.

8. How much does it typically cost to repair OBDII code B2794?

- The cost of repairing this code can vary depending on the underlying cause, but it may involve replacing the key fob, reprogramming the immobilizer system, or addressing any wiring issues, which can range from moderate to expensive.

9. Can a locksmith help with fixing OBDII code B2794?

- Some locksmiths may have the expertise to assist with reprogramming keys or addressing issues related to OBDII code B2794, but it is recommended to consult with a mechanic or dealership for a comprehensive diagnosis and repair.

10. What should I do if OBDII code B2794 keeps coming back after repairs?

- If the code persists even after repairs, it is crucial to reevaluate the diagnosis and ensure that all possible causes have been addressed. Consulting with a professional automotive technician may be necessary to resolve the recurring issue.