No power to the front drive shaft in 4WD

JORDAN55BIRD

MEMBER
1999 CHEVROLET SUBURBAN
5.7L
V8
4WD
AUTOMATIC
260,000 MILES

Having a hard time diagnosing issues related to my 4x4. Both the front axle actuator and encoder motor on side of transfer case have been replaced and as far as I can tell my listening to them are functioning. I’ve got the electronic buttons for 4 wheel drive and they appear to be working as they should. When I put the truck into 4 hi it sounds like it engages but the front two wheels have to power to them. Same thing happens in 4 low. Is there maybe something I could check on the transfer case itself? Any helps appreciated.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,709 POSTS

Hi,

Have you confirmed there is power to the front axle actuator? If so, there is a chance the transfer case control module isn't providing a ground path for the actuator.

Do me a favor. I attached diagnostics related to a front axle actuator not working. Take a look through them and let me know if it is something you are comfortable doing.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Let me know.

Take care,
Joe

See pics below.

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