[Fixed] Just changed battery, now 1991 Bentley Mulsanne S asks for a PIN code

3870 views - Last reply: September 20, 2024
This topic is closed for new replies.

How do I retrieve the key code for my 1991 Bentley Mulsanne S to program a key?

Hello! We've developed a VIN-based tool to help you get your key code for the 1991 Bentley Mulsanne S. Check it out here: VIN Key Code Generator.

Replies (6)

I’m not alone! My 1991 Bentley Mulsanne S is doing the same thing.

Trying to avoid reprogramming costs for my 1991 Bentley Mulsanne S. This is a lifesaver.

This looks helpful for those of us with a locked-out 1991 Bentley Mulsanne S.

This just might solve my 1991 Bentley Mulsanne S's ignition issue.

Really need the key code for my 1991 Bentley Mulsanne S, thanks for sharing!

Hope I’m not too late to try this on my 1991 Bentley Mulsanne S.

Check the news !

Annual Muscle Car Meetup
🏎️ Local Meetup: Annual Muscle Car Meetup
From daily drivers to show queens

🗺️ Where: Community College Campus
When: March 14 @ 12AM-6PM

Event features:
Club Displays | Trunk Swap Meet

🔩 Forum Members: Don't forget to tag your photos #OurForumName 👍

🔧 Hands-On Engine Tuning Workshop

👨‍🔧 Instructors:
• Race Engineer Emily Torres
• Suspension Guru David Klein

🛠️ Hands-On Activities:
• Panel beating and dent repair
• 4-hour intensive training
• Personal coaching

📝 Skills Covered:
Paint decontamination | Polishing | Protective coatings

🚗 February 27, 2026 at 1:00 PM (4-hour)

🔥 Certificate of completion provided!

Workshop: Hands-On Engine Tuning Workshop
Race Car Setup Seminar

🏁 Race Car Setup Seminar

🔧 Instructor: Turbocharging Specialist Marco Rodriguez

💻 Workshop Includes:
• Hands-on ECU flashing sessions
• 6-hour comprehensive hands-on training
• Cam profiles | Compression ratios | Octane requirements

📈 Bonus: Custom tune file included

⏱️ Next Session: February 24, 2026 at 3:00 PM

Customize Your Tuning Focus:

🚀 Performance Mod Cost Estimator

FYI: Many performance shops offer package deals for common upgrade paths

Vehicle Information

Modification Information

Additional Options

🔑 Car Key & Fob FAQ

Common questions about key programming, fob issues, and replacement options

Security Systems
An anti-theft system that prevents the engine from starting unless it detects the correct transponder chip in the key. The chip sends a unique code to the car's computer when you turn the ignition. No match = no start, even with a physically matching key.
Key Tip: Some locksmiths offer mobile key programming services
Key Fob Issues
This typically indicates: weak fob battery (replace first), damaged fob antenna, or issues with your car's receiver (often in the door handle or rearview mirror). Environmental interference from other electronics can also reduce range.
Key Fob Issues
Common causes: dead battery (most common), water damage, internal circuit damage, or the fob lost synchronization with your car. Try replacing the battery first. If that doesn't help, the fob may need reprogramming or replacement.
Key Programming
Common reasons: wrong key type for your vehicle, anti-theft system needs reset, low car battery voltage during programming, or the key isn't properly synced. Some cars also have programming limits (only 2-4 keys can be registered).
Key Tip: Store your key code separately from your keys
Security Systems
An anti-theft system that prevents the engine from starting unless it detects the correct transponder chip in the key. The chip sends a unique code to the car's computer when you turn the ignition. No match = no start, even with a physically matching key.
Key Tip: Keep spare keys in a faraday bag to prevent signal amplification theft
Key Fact: Smart keys use radio frequencies between 125 kHz and 2.4 GHz

🔑 KEY SERVICES CLASSIFIEDS

Lost Car Key Replacement
$120+
Posted: Feb 9, 2026
Lost all your keys? We can cut and program new ones even without originals. Dealership alternative at 40% less. Proof of ownership required. Serving all major brands.
Call: 600-599-9386
Car Key Extraction Service
$45+
Posted: Feb 5, 2026
Broken key stuck in ignition or door? We can remove it without damage and make new keys same day. Emergency service available 24/7 for lockouts.
Call: 845-439-8880
Fleet Key Programming
Call
Posted: Feb 13, 2026
Commercial key services for businesses with multiple vehicles. Bulk discounts available. We can handle all your company cars, trucks, and fleet vehicles.
Call: 358-462-6196
Dealer Alternative Key Service
40% Less
Posted: Feb 13, 2026
Same quality as dealership without the markup. We have the same programming tools but charge significantly less. All major European, Asian, and domestic brands.
Call: 494-789-8916
Ads refreshed daily • Licensed professionals • Mobile services available

🔑 Upcoming Key & Immobilizer Services

Seminar
Feb 17, 2026

Car Security Certification Course

by The Key Lab
Hands-on training for programming transponder keys, smart keys, and fobs using professional tools
Workshop
Feb 28, 2026

Transponder Key Tech Day

by Car Key Solutions
Become certified in vehicle security systems with our intensive 2-day course
Seminar
Mar 12, 2026

Lost Key Solution Roadshow

by Car Key Solutions
In-depth class covering push-to-start systems and proximity key programming techniques
Seminar
Feb 14, 2026

Anti-Theft System Demonstration

by Locksmith Pro
Solutions for when all keys are lost - from code pulling to immobilizer resets

Need immediate service? Call our 24/7 hotline: 1-800-KEY-HELP

Want to list your key service? Join our provider network

Last posts on the forum