Transfer Case Module Part Number

Recently my 2000 Blazer LT with Autotrac "Service 4WD" indicator light lit up, as it routinely lights now after about 90 seconds of turning on the ignition key. Additionally, the transfer case would shift from 2HI to AUTO 4WD, but never into 4HI, 4LO or Neutral. Once in AUTO 4WD it would never shift back out unless I disconnected the 4WD indicator switch from the front axle. Thus, the actuator seems to work (partially).
I was able to swap out the transfer case shift control module with a co-workers nearly identical 2001 Blazer LT and the Autotrac system now functions normally.

The part number on the module, in both vehicles, is 15748800.
This part number does not exist at gmpartsdirect.com, 1aauto.com or rockauto.com. However, a search for this module on gmpartsdirect.com lists part number 12577412.

Can anyone confirm that the replacement transfer case shift control module for my application (2000 Blazer LT with NVG 236/246-NP8, Two-Speed Automatic) is part number 12577412?

Since I can't find this original module part number from any supplier, I assume that this new part number is an "improved replacement part"
as the original had a high rate of failure?

Thanks for your help!

Cujster
(S.E. Michigan - where trucks and SUV's are required due to the normal broken down state of our highways and byways)

I've answered my own question since my initial post on this topic.

The original transfer case control module part number is: 15748800
This module was used for all NVG-236/246 transfer cases.
GM has since replaced this module with an updated version
(newer chips and software), part number: 12577412

A GM dealer will charge you about $410 for this part.
GMPartsdirect.com sells it (including S&H) for $278

For those of you looking for this transfer case computer module (part number 12577412) a high number are available on ebay at $99 plus shipping (7/27/08).

http://cgi.ebay.com/ebaymotors/GM-Transfer-Case-Control-Module-Shift-15748800-12577412_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el 1116QQitemZ320278703805

Thanks for posting that info but this thread is almost 4 years old. Please check the dates before posting.