Service 4wd light turned on

2003 CHEVROLET SILVERADO
130,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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BWILKINSON05
  • MEMBER
  • 68 POSTS
My service 4wd light came on, I have completed the following:

Removed and sanded ground wire on driver side of frame (outside).
Installed new 4wd drive actuator.
Installed new 4wd switch.

How do you recommend I proceed?

Thank you,
Bret
Jan 30, 2021 at 4:01 AM
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JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,240 POSTS
Hi Bret, often times a faulty wheel speed sensor can cause the light to turn on. Are any other lights on? Have you tried scanning the can-bus system? CAN stands for controller area network. Basically, all the computers and modules are tied together via a few wires. By scanning the "can" it should identify any issues regardless of the module on the vehicle.

Here is a video showing how it's done:

https://youtu.be/InIlnsjOVFA

I would start by doing the scan. If you can't, let's confirm that all wheel speed sensors are working. Here is a link that explains how to do it:

https://www.2carpros.com/articles/abs-wheel-speed-sensor-test

Let me know what you find or if you have other questions.

Take care and God bless.

Joe
Jan 30, 2021 at 9:43 AM
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