A computer implemented method for identifying real time health status rating parameters of an electrical system of a vehicle by use of a vehicular telemetry system comprising a telematics hardware device and a remote device (19, 20), the telematics hardware device comprising a processor (31, 32), a memory, firmware and communications capability, and being configured to monitor at least one electrical system component from at least one vehicle, to log component data of the at least one electrical system and to communicate a log of electrical system component data to the remote device (19, 20), the remote device (19, 20) comprising a processor, a memory, software and communications capability, and being configured to perform the method comprising: receiving a plurality of voltage signals indicating a change in voltage of a vehicle battery at times associated with a plurality of crankings of a starter motor of the vehicle; determining for each of the plurality of voltage signals a minimum voltage of the voltage signal and generating a plurality of minimum voltage signals for a time period; characterized in that the method comprises determining a minimum operational threshold voltage value (Vmin) representative of a failing health condition of the electrical system during cranking of the starter motor and a maximum operational threshold voltage value (Vmax) representative of an optimal health condition of the electrical system during cranking of the starter motor, wherein the minimum and maximum operational threshold voltage values (300, 310) are determined from historical vehicle battery data having a distribution curve associated with life cycle of the vehicle battery from an optimal health condition to a failing health condition; generating for each of the plurality of minimum voltage signals normalized real time electrical system health status rating parameters based on normalization of the plurality of minimum voltage signals with the minimum and maximum operational threshold voltage values where the normalized real time component electrical system health status parameters are one of a probability and numerical value representative of the probability, wherein each of the normalized real time electrical system health status rating parameters of the vehicle is derived from: H = V-Vmin / Vmax-Vmin, where V represents one of a filtered and a non-filtered minimum voltage of the voltage signal, and when V is non-filtered said each of the normalized real time electrical system health status rating parameters is subsequently filtered; and communicating the normalized real time electrical system health status rating parameters to an owner of the vehicle. receiving a plurality of voltage signals indicating a change in voltage of a vehicle battery at times associated with a plurality of crankings of a starter motor of the vehicle; determining for each of the plurality of voltage signals a minimum voltage of the voltage signal and generating a plurality of minimum voltage signals for a time period; characterized in that the method comprises determining a minimum operational threshold voltage value (Vmin) representative of a failing health condition of the electrical system during cranking of the starter motor and a maximum operational threshold voltage value (Vmax) representative of an optimal health condition of the electrical system during cranking of the starter motor, wherein the minimum and maximum operational threshold voltage values (300, 310) are determined from historical vehicle battery data having a distribution curve associated with life cycle of the vehicle battery from an optimal health condition to a failing health condition; generating for each of the plurality of minimum voltage signals normalized real time electrical system health status rating parameters based on normalization of the plurality of minimum voltage signals with the minimum and maximum operational threshold voltage values where the normalized real time component electrical system health status parameters are one of a probability and numerical value representative of the probability, wherein each of the normalized real time electrical system health status rating parameters of the vehicle is derived from: H = V-Vmin / Vmax-Vmin, where V represents one of a filtered and a non-filtered minimum voltage of the voltage signal, and when V is non-filtered said each of the normalized real time electrical system health status rating parameters is subsequently filtered; and communicating the normalized real time electrical system health status rating parameters to an owner of the vehicle.