Manager Forum

I have a 2006 Silverado 1500 4X4 that intermittently shows the "Service four wheel drive" warning. Had B2725 - Mode switch circuit malfunction code.

Inspected wiring for chafing and grounds. Warning was not displayed while here. Research in iatn and napafix indicated most common issue with this condition is encoder motor. Replaced encoder motor 11/9 (NAPA part - probably A-1 Cardone ). Have used these in the past with success. Everything functioned at that time. Delivered vehicle.

Yesterday warning came on again. Same code. No warning while here and everything functions.

One of my techs has a 2001 Silverado that he bought new and he says his does this same thing. While under warranty dealer replaced encoder, switch and tccm module. He says that when warning comes up if he cycles key it goes away and everything is good.

Any experience or insight from the troops?

Switch on the dash

agreed with above

Installed a new function switch today. Will let customer drive for awhile and see if it cured her issues. I Will update when I know more.

has this been offroaded atleast once? check all wires going to connectors.

This customer came in last evening with a good report and paid the bill. Has only used 4X4 once since replacing the dash switch. It functioned as commanded and no warning lights have come on.

thx for the update

great news......thanks for posting