2 wheel drive/4 wheel drive light goes out
 

Hi Guys (and Girls),

I've been lurking on the forum for awhile and I finally have a need to post a technical question (lucky me). I have a 2004 Blazer LS that seems to be functioning fine but I have an intermittent problem. The lights on the pushbuttons to select 2 wheel drive/4WD hi/4WD lo sometimes go out after I have been driving the vehicle for awhile. It seems to shift in and out of 4 wheel drive like its supposed to, I don't have any Service Engine or Service 4 wheel drive lights on so it doesn't seem to be throwing up a code. Any ideas. Is this nothing to worry about or should I expect a big repair in the near future.

Thanks in advance.

Bob

If you have the 3-button switch in the dash (NV233), then you won't see a 'service 4wd' message.

If that is the case, use the thread below to check the codes from the TCCM:
OBD2 Non-Automatic Transfer Case Diagnostics

You could also remove the passenger side kick panel and check the connections to the TCCM for corrosion.

what is the best way to clean corrosion?

First, this is a nine year old thread, lol. Let it rest in piece!

I've always had decent luck cleaning corrosion off with a wire brush or maybe some sandpaper if it isn't too bad. If it's really bad, consider replacing the component