Four-wheel drive not engaging?

2000 CHEVROLET BLAZER
106,000 MILES • 4.3L • 6 CYL • 4WD • AUTOMATIC
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PDW
  • MEMBER
  • 6 POSTS
The 4WD is not engaging when the button is pressed, however 4x4 button does light up and steadily burn, not flashing. No strange sounds or anything unusual, just won't engage. Thanks in advance.
Jan 9, 2024 at 5:04 PM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,194 POSTS
  • ASE Certified Mechanic
Hi,

There is a vacuum actuator for the front axle under the hood on the passenger side. I need you to inspect the vacuum hoses to and from it for damage, leaks, or if they are disconnected. Follow them to the actuator on the differential. When requesting 4wd, see if there is a vacuum provided.

I attached a pic of the actuator. Note, there should be an electrical connector as well to turn the 4wd light on in the vehicle. Let me know what you find.

Take care,

Joe

See pic below.
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Jan 9, 2024 at 9:34 PM
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