Vehicle Speed Sensor Calibrator Module

The Vehicle Speed Sensor (VSS) calibrator module is a solid-state device that is used to change the signal from the speed sensor to a digital signal. The VSS calibrator module will change the signal from the speed sensor to a signal containing 4000 Pulses Per Mile (PPM) for the instrument cluster. The vehicle speed sensor calibrator module is matched to the final drive and tire size of each vehicle. It must be replaced with the proper module to match the final drive and tire size of that vehicle. If the final drive or tire size is changed for any reason, the module must also be changed to continue to produce an accurate speedometer/odometer reading. The incorrect module will also affect the anti-lock brakes, Vehicle Control Module (VCM), and the cruise control module. For diagnostic information, refer to SECTION 8A.