Service AWD light

[astrojohn]

The Servicde AWD light comes on at intermittent times. I could drive it somewhere, shut it off, and when I start back up, the light is on.
When that happens, I notice the light on the dash, blinks about 4 times, and I hear a click of a relay or signal flasher each time the light flashes. I hear it under the dash on the driver side.
I've read that this condition is caused by corrosion or debris in the plug in, on the transfer case.
I've also read there's wires corroded behind the battery? What could be there for the AWD?
Does anyone know how to scan for the codes for the awd? Does anyone know what all the codes for awd are?
I do alot of the work myself, and would like to tackle this one too, just need some advice, and information.
If anyone has the wiring circuit diagram for the awd and transmission, I would like that also.
Thanks to all who take the time out to help.

[LiftedAWDAstro]

I don't think the service AWD line of codes can be scanned with a basic code reader. I think it needs a higher tech tool.

What you can do in the meantime is to start at the t-case and pull all connectors and inspect/clean/lube with di-electric grease and work your way back through the harness. Under the dash is a TCCM (transfer case control module) that is probably making the noise you hear. As for any connections behind the battery, you can remove it and take apart and inspect those connections as well. You might get lucky and find an issue and all you'll be out is some time.

[astrojohn]

Has anyone ever had the transfer case motor go out. If you did, what were the symptoms?
Did your service awd light come on, when, and how often.
Mine goes out overnight, and when I drive to work in the morning. On my way home, it will come on, and stay on.
I stop to do a few errands, and when I re start, it comes on.
If the motor is going out, I would like to tackle it before this winter.
Is there anything I need to know in the change?

[LiftedAWDAstro]

There have been many who have changed the motor. Start searching and reading through the threads.