Is the 4 wheel drive light on on my Trailblazer?

2002-2005 Chevrolet TrailBlazer, TrailBlazer EXT 2002-2005 GMC Envoy, Envoy XL 2004-2005 GMC Envoy XUV 2002-2004 Oldsmobile Bravada with Four-Wheel Drive (4WD) Condition Some customers may comment that the Service 4WD light is on, the 4WD system is inoperative or the 4WD switch indicator lights are blinking. Service Diagnosis

What to do if your Chevy Trailblazer does not engage?

Make sure the tab (1) on the encoder mates with the notch (2) on the shaft. If the encoder tab is not aligned with the output shaft, rotate the encoder inner ring by hand to mate properly. Press the encoder fully onto the shaft and into the housing. Important:

Why is my 4 wheel drive light not engaging?

If you don’t shift it into neutral, the 4wd light will continue to flash and won’t get into gear. Seems to be a common occurrence on these trucks. Dodge dealers recommend engaging 4-lo, then back in 2-wheel drive, then back in 4-wheel drive hi (4H). This sequence apparently resolves the problem.

When did Chevy Blazer get electronic control 4WD?

But this was on an 1997 Blazer with Electronic control 4wd, so lets hope they improved the system since then. As was stated earlier in the thread, I don’t think it’s parts, I think it’s the switch tnpartsguy spoke of, since the light on the switch was off when the notice light was on, and vice versa.

Why is my Chevy Trailblazer not engaging 4HI blinking?

First thing to do is with engine off and ignition on, switch from 2HI to 4HI and listen for two distinctive noises. If you hear both, more than likely the front spline disconnect assembly (at the front axle) is defective. In order to troubleshoot the 4WD system, you need to have an understanding of the whole thing, it is not a DIY item.

Why does my Trailblazer 4WD make a noise?

There are two actuators that activate the 4WD components, one is for the Transfer case modes and the other is for the front axle disconnect. Both of these actuators make a distinctive noise (motor noise) when activated.