Year to year changes?

[bigskypc50]

Couple quick questions 

How different are the cars between 2001-2003? I have a service manual for 2001 will that also work for the most part on a 2002?

I am looking at 2002 3.5 and it appears to have heated seats but there is what looks like a T/C button on the console, but I thought only the 4.0's had T/C buttons, what other button would be in the same place?

[Paulaurora]

2001 and 2003 are same cars 2001-2002 came with v6 and v8 2003 only came with v8. T/C was offered in v6 as well but was an option V8 has t/c as standard . 2001 v6 and v8 rust very easy compare to 2002 -2003 ver. 2002-2003 came with analog/digital on-star system and navigation 2001 doesn't support it. so v6 2001-2002 manual will be the same or v8 2001-2003 is same thing .