Service 4WD message

[pppr]

I have a 2000 model Chevy Suburban with 4wd. My service 4wd light keeps coming on and I would like to know what it means and how to reset the light.
Thanks,
Ron

[777stickman]

Ron: The "service 4wd" light is triggered by the Transfer Case Control Module picking up something wrong with the transfer case system. You'll need access to a code scanner to determine the problem. The light will go out when the problem is identified and fixed...........Steve

[madfinn]

I had the same thing with my 2000, was some sort of relay, labor and parts were about $70.

[dkraines]

My Experience,

Just bought a 2000 'burb' with 62K miles. After 2 days the "SERVICE 4WD" light came on, and stayed on until the ignition was turned off. I didn't worry about it until it came on a few more times in the next 100 miles. Also the switch did not work very well, I might have to press the button 10 times to get it to switch from 2X to 4X hi.

After researching Google, most people say the problem is with cold solder cracks in the pushbutton switch. After reading all the issues people had with dealers mis diagnosing this problem (paying 100 to 600 dollars), I thought I would resolder the PCB and try my luck at a free solution.

It took about 15 minutes:

1. Pulled the switch out (most people complain about the plastic dash appearence, but I had the switch out in 2 minutes, because the dash is just snapped in, as is the plastic switch). I have a new appreciation for the plastic dash.

2. Pry'd the switch apart

3. Desoldered the 2 harness connectors with solder wick

4. Resoldered with USA quality solder

5. Put everything back together

...and now my pushbuttons work the first time(I did about 20 tests including neutral) and I have gone 20 miles without the "SERVICE 4WD" light.

Call me a risk taker, as the manual states "serious" damage consequences for not having this professionally diagnosed. Your mileage may vary.

Funny how the Chevy dealer says you don't need to do anything for 100K miles except change the oil. I also had to fix:
1. The water pump (bearing was leaking through the hole)
2. power steering pump (leaking)
3. front shocks (leaking)
4. brake fluid (black from piston wear)
5. transmission (fluid was not bad, but not clean)
6. CD skipping, had to clean the laser
and just because I didn't know the history of the vehicle:
7. replaced the oil the diffs and TC (GM syn. TC fluid is ridiculously expensive)
8. cooling - I don't buy the "no change for 150K" dexcool hype

Air is coming through the passenger side door, I will look at this later.

Other than that the rig seems fine.