Patent ID: 8618809

Claim:
A method for detecting electrical isolation between a bus terminal and ground, or chassis reference, on a vehicle, the system comprising: providing a bus terminal isolated from the ground and chassis reference during normal operation of the vehicle; applying a first current to the bus terminal; detecting a first level of the first current, or a corresponding observed voltage level based on the first current, that flows or exists from the bus terminal to ground, by compensating for a range in the detected first level by applying a corresponding compensating voltage level to a resistive network coupled to a level detector for detecting the first level based upon certain observed reference voltage levels; and estimating a first isolation level between the bus terminal and the ground, or the chassis reference, based on the detected first level, wherein the compensating voltage places the first level within a target measurement range for detection by the level detector, where the target measurement range is consistent with an input voltage range of an analog-to-digital converter coupled to the level detector.