Four wheel drive not engaging

2008 CHEVROLET SUBURBAN

257,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC

MOUNTAINMAMA

MEMBER
1 POST

For two months my SUV was stuck in 4wd with a service 4wd error message. Then it stopped working altogether. No indicator lights. Fuses replaced, actuator replaced, transfer case computer module replaced. Still no indicator lights, still an error message, still no 4wd. What can possibly still need to be replaced?

Feb 6, 2021 at 7:46 PM

SEVAG P

✓ASE Certified Mechanic
405 POSTS

hello,

It could be from the switch that actuates the 4 wheel or the harness of the actuator, to make sure read the fault codes and send to us.

check our link below how to read fault codes.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Check visually connectors of the 4 wheel switch, transfer gear actuator switch for proper installation and if they are clean, check the diagrams below.

let us know what happens with you.

thank you.

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Professional Diagram for 2CarPros Members
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Feb 7, 2021 at 7:10 AM

Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.