on position, not necessarily starting the engine. Getting the engine started is needed to get certain parameters, however, like RPM.
2) If your system is connected to the OBD while you are cranking the starter, you may see some sharp voltage spikes. Some circuits, like the SparkFun's OBD-II UART, are able to cope up with these spikes. In my experience, although the voltage regulator IC heats up, the device hasn't shown any sort of malfunctioning.
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