S15/T15 Sonoma P/U 4WD V6-4.3L VIN X (1998)
Control Module: Description and Operation
New Venture Gear 136 Transfer Case
TRANSFER CASE SHIFT CONTROL MODULE
The transfer case shift control module uses the VIN information for calculations that are required for the different calibrations used based on axle
ratio, transmission, tire size, and engine. The system does not know which calibration to use without this information. The direct battery supply line
(CKT 1640) provides the power to the module and motor circuitry.