4wd service light comes on but lights on switch work

[tamegm]

could somebody direct me to the proper thread, service bullitine or give me info on my current situation?

my service 4wd light has come on at couple of times this december as it has gotten cold but the lights on the switch are fine and still switched. when I turn it off the tb and back on the light goes off. no codes on the obdII.:excited:

[Vartz04]

you wont get chassis codes on an OBDII, a dealer has to scan for those codes.

Most people the switch/lights stops working all together. Maybe your switch contacts are dirty? Im not sure next time its on drive to the dealer and have them pull the codes

[the roadie]

Dirty or oxidized contacts from underuse could easily cause this. The contacts aren't the kind where each one connects to a different wire that goes to the control module. Each switch position selects a different value resistor, and the control module measures the voltage coming back on the sensing wire, and infers what position the switch must be in. An oxidized contact can make the resistance seem higher than it really is, and then the control module expresses its confusion by setting a code and putting on the "service" light.

I'd try turning the switch back and forth a hundred times just to clean up the contacts a bit.

[Vartz04]

Awesome, My guess was right.

Now if that happens every day this week, ill have a great GPA for the semester. I hate finals