1999 Buick century anti lock signal and trac off displayed when traveling over 60 miles per hour

Find and use a code reader and check the trouble codes.

From what I have researched the core runs 50 - 60 USD. It appears that accessing the core is not as difficult on this model as some others, and I would estimate that a shop would charge about 2-3 hours labor to do it. You would also have the cost of replacement coolant as well and possibly new hose clamps depending on the condition of the existing ones. If you are moderately capable, it is a job that can be done DIY and there are a few Google links explaining step-by-step how to do it. A shop (US) current charges 70-100 USD per hour for labor, so you can do the math.

Now you diagnose the ABS Braking System issues

Sounds like you need to replace your speedometer cable that runs from your dash to your transmission.

Well Carol, to be quite honest, your problem is not easy to DIY and it probably won't be super cheap to fix. The "Trac OFF" light indicates that the Traction Control is not on or not functioning properly. This usually means that the TCM or Traction Control Module is bad. The "Anti Lock" light indicates that you most likely have one or more wheel sensors that are bad, or the ABS (Antilock Breaking System) has a bad module. You may also want to check out some forums on the buick century. It seems as thought the problems you are experiencing, are quite common in the Buick Century. Here are a few links that may help you narrow it down and possibly find a manufacturers recall on the problem. Hope this helps.

NHTSA > http://www-odi.nhtsa.dot.gov/

NHTSA > TSB > http://www-odi.nhtsa.dot.gov/tsbs/tsbsearch.cfm

NHTSA > MFG RECALL > http://www-odi.nhtsa.dot.gov/recalls/recallsearch.cfm

Hello: Check the brake light switch. It is mounted on/near the brake pedal before you attempt to repair brake and anti lock lights.

You will need to have the computer scanned for codes, the codes will tell you where the problem is, when the abs light is on it will turn on the other lights the ser light and trac light, once the abs if repaired the other lights will clear, the most common problem with these is one of the wheel speed sensors go bad, hope this helps.

I just put in new fron pads in my 2000 buick century and the track off and the anti lock brake light and the service engine soon stays on

BAD WHEE BEARING AND PROBABLY THE PLAY FROM THE WHEEL BEARING HAS DAMAGED THE SPEED SENSOR FOR THE ABS

Are you sure of the lights? If it is Service VEHICLE Soon, in addition to Trac Off and Anti Lock, it is most likely one of the four wheel hub assemblies. These are sealed bearing units that feed a signal to the computer for the ABS brakes and the tire pressure system. I had one go out intermittently (seemed to be aggrivated by humidity/moisture). I had it replaced, and another one is going out. It seems like they are a bit prone to failure. My Century has 101K, and I experienced the first one around 75K miles. Unfortunately, to tell which one is failing requires a scan tool above and beyond the simple one that most parts stores use. BTW, there was a problem that was fixed just prior to 2002 that was caused by the signal wires going to the left front wheel hub being worn through and shorting. I believe this problem was fixed by 2002.