Computer replacement

2005 CHEVROLET TRAILBLAZER
190,000 MILES • 4WD • AUTOMATIC
Avatar
AKARVOLA
  • MEMBER
  • 3 POSTS
I am getting codes that lead to a bad computer. I am going to the junk yard to get one. does it make a difference if the one I pull comes from a 2wd since mine is a 4wd?
Dec 23, 2018 at 8:53 AM
Advertisement
Avatar
ASEMASTER6371
  • CERTIFIED EXPERT
  • 52,796 POSTS
Good afternoon.

Yes, it matters. you need the exact number from the old one to the one you are looking at.
You will also need to have it flashed to your VIN number and the keys reprogrammed.

Lets back up. what were the codes that make you think you have a bad PCM?

Roy
Dec 23, 2018 at 11:44 AM
Avatar
AKARVOLA
  • MEMBER
  • 3 POSTS
I just swapped the computer and did a simple key relearn process online and everything seems to work fine. Only issue that I notice is the 4wd doesn't show on the dash when it engages. thank you though.
Dec 23, 2018 at 4:17 PM
Advertisement
Avatar
ASEMASTER6371
  • CERTIFIED EXPERT
  • 52,796 POSTS
You are welcome.

The four wheel will not work until you have it flashed. you need to tell the PCM it has four wheel drive.

Roy
Dec 23, 2018 at 4:30 PM
Avatar
AKARVOLA
  • MEMBER
  • 3 POSTS
when I switch it to 4wd you can here it engage and the same with 4 low.
Dec 23, 2018 at 4:58 PM
Avatar
ASEMASTER6371
  • CERTIFIED EXPERT
  • 52,796 POSTS
Okay, you are lucky it is recognizing the four wheel drive.

I still think it needs to be flashed.

Roy
Dec 23, 2018 at 6:51 PM