Digital Ratio Adapter Controller (DRAC)
NOTE:
Vehicle speed sensor buffer is an internal part of the DRAC and is not serviceable. References to buffer are referring to DRAC.
Digital Ratio Adapter Controller (DRAC) is a solid-state device used to change AC voltage signal from the VSS to a digital signal for speedometer operation.
The DRAC is matched to the final drive ratio of each vehicle. If the final drive ratio is changed for any reason (i.e., tires or gears), the DRAC must be replaced to maintain accurate speedometer/odometer reading. See SPEEDOMETER CALIBRATION.
NOTE:
Incorrect speedometer calibration will affect operation of Rear Wheel Anti-Lock (RWAL) Brakes, Electronic Control Module (ECM) and Cruise Control Module (CCM).