2000 cavalier stock stereo

This is a very confusing system to understand and I receive at least 10 calls on a day on this very subject. Let me explain this so you all understand and please understand I am not biased towards any way. Do these vehicles as you may, it doesn't matter to me.

On a class 2 data system which started in 1996 on Cadillacs, 2000 on GM's, when you start the vehicle, the computer sends out a signal to all pieces on the data line. Once the first module on the data system receives a signal, it then sends back a signal to the computer to let it know it's good. From there it goes to the next module and so on. Now if a module was not there or went defective, it may send the computer into a frenzy. Anything on the data bus after that piece will not work as the computer does not go farther than the fault. That is why the most important modules like fuel and such are first on the data bus. Most vehicles do not put important modules behind the radio on the data bus, but Cadillac and Pontiac are known to do so. So this is why the more features your vehicle has, the more problematic it can be. Now what nobody knows and GM does not announce is where  the airbag is on the data bus. Another problem according to calls I receive is when you leave the radio out or the computer is an a frenzy, the dealerships computer interface will not allow it to access the system. False or not I do not know , but I do receive calls that say this from people that do not use the proper harness. I know dealerships will use any excuse to void the warranty.

Now that's class 2 in a nutshell. Stay tuned for the new and improved GM LAN system!

For those who would like to use a wiring harness to keep the delayed accessory feature, keep chimes, turn Bose amps on, and not have problems when your car is being serviced, use these part numbers;  GMRC-01 for the base system, GMOS-01 for base systems with On-Star, GMOS-02 for the Bose amped systems with or without On-Star, GMOS-03 for the systems with a Delco or Monsoon amp.

And of course we have the relocation harness, 70-2003t with the SP-2003 speaker and the On-Star relocation harness, 70-2005.

One side note before I leave, not all 2000 GM's are class 2. In 2003 most are but not all. A common vehicle I get that is not is the S-10. Also, RDS does not mean it is class 2. This is a tuner feature. An easy way to tell if it is class 2 is to check for an accessory wire. If it does not have one, it is a class 2 vehicle(Corvette is an exception, it is not).

I hope this clears up any questions anyone has and if you have any more questions please post back.                                                                                                                     

peripheral now has a harness that you can use and not have to retain the factory radio. they are not cheap but you save so much time on the installation.

here is the link:

http://peripheralelectronics.com/periph_products/cd_changer_autos/instructions/peswix%20inst%209-23-02.pdf

opps, sorry wrong link....

here is the correct one:

http://peripheralelectronics.com/2002/onstar.asp