TextHow the Century Key System Evolved
Early W-Body Transponder
This is where GM started getting serious about theft prevention on the Century. Your 1997 to 1999 model uses a Texas 4D (ID44T) transponder chip embedded in the key head, paired with the VATS/Pass-Key III immobilizer system. It is a standard transponder key with no remote buttons built in, so your lock and unlock buttons live on a separate fob.
Remote Head Key Arrives
GM combined the transponder and the remote into one piece for the 2000 to 2002 Century. Same Texas 4D (ID44T) chip, same Pass-Key III security, but now your lock, unlock, and trunk buttons are built right into the key head. One key does everything, which means one key to replace if something goes wrong.
Late W-Body Refinement
The final Century years kept the same remote head key with the Texas 4D (ID44T) chip and Pass-Key III immobilizer. Remote keyless entry became standard equipment across the lineup. Programming still requires OBD-II access and a security PIN, which we pull on-site with our Autel IM608.
Which Key Does Your Century Use?
Your key is a standard metal key with a thick plastic head that holds the transponder chip. The remote fob is a separate piece you carry on your keychain.
Everything in one key. The lock, unlock, and trunk buttons are built into the key head along with the transponder chip. One piece to carry, one piece to replace.
Same remote head key style as the 2000 to 2002 models. Three buttons, standard blade, and a Texas 4D chip inside. Remote keyless entry came standard on these years.
Pricing by Generation
Price includes the key blank, cutting, transponder programming, and remote programming, all done on-site at your location.
EZ Car Keyz vs. the Dealer
We carry the same professional programming platforms the dealer uses. The difference is we bring them to your driveway for about half the price.
Skip the Dealer - Call (805) 790-8162Common Buick Century Key Problems
Transponder Chip Failure
The Texas 4D chip in your Century key head wears out over 20-28 years and stops talking to the Pass-Key III module. The car cranks but will not start. We test the chip on-site and cut a new transponder key if it is dead.
Key Fob Battery Drain
Dead fob? First we check the CR2032 and clean the contacts. Corrosion builds inside older remote heads, especially coastal Oxnard and Ventura. A $3 battery and contact cleaning usually brings it back. Board fried? We replace the whole key.
Ignition Cylinder Wear
Key goes in, you turn it, nothing. Or it fires on the third try. Worn ignition cylinders are common on high-mileage Centurys. We diagnose whether the problem is the cylinder, the key, or the Passlock sensor, and fix it on the spot.
Immobilizer ECM Fault
Owners assume they need a new key when the body control module is glitching. On 2003-2005 Centurys, the BCM loses comm with the transponder reader, throwing a false security lockout. We read the codes first; sometimes a reset is all it takes.
Can You Program a Century Key Yourself?
Yes, you can program the remote lock and unlock buttons yourself using the door unlock switch method. This only pairs the remote; it does not program the transponder chip that starts the car. You still need a locksmith for that part.
Yes, the ignition cycle method lets you pair remote buttons at home. Turn the key ON, OFF, ON, then open and close the driver door and hold the lock and unlock buttons until you hear chimes. Again, this is remote only. The transponder still needs professional programming.
If you already have one working key, GM's 10-minute relearn procedure can add a new transponder key. Insert the working key, turn to ON, remove it within 10 seconds, insert the new key, and watch the security light. It is timing-sensitive, and the new key must already be cut to match your ignition.
No. If you have lost every key, there is no DIY path. All keys lost requires OBD-II access, a security PIN, and professional tools to reprogram the BCM. Call us at (805) 790-8162 and we handle it on-site.
How It Works
Call Us
Call (805) 790-8162 and tell us your exact year and what happened.
We Come to You
Wherever you are in Ventura County, from Simi Valley to Camarillo, we drive to your location.
Cut and Program
We cut your new key on-site using a GM standard cutter, then program the Texas 4D transponder chip to your Century's Pass-Key III system through the OBD-II port using our Autel IM608.
Related Services
Did You Know?
Most people do not know this: the 1997 to 2005 Buick Century was the last W-body platform sedan to offer full six-passenger bench seating. While other GM sedans moved to bucket seats and center consoles, the Century held on to its front bench as a nod to its family hauler roots. It was a quiet rebellion against the sport sedan trend, and families loved it for exactly that reason.
KEY REPLACEMENT ACROSS ALL OF VENTURA COUNTY
We come to you, anywhere in Ventura County. No shop visit, no towing. Our mobile locksmith arrives at your home, office, or roadside.
Buick Key Service Demo
Watch a Buick key get cut and programmed at the customer's location.
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