which terminal powers the scanner on the obd on a 1994 chevy 2500 4x4
The OBD connector is a suggestion and companies are not forced to adhere to all standards and formats. Many OBD scanners can run from power at the OBD connector while others must run from an internal 9V battery. Only some connector pins are standard and not every OBD connector can provide power to drive an OBD scanner.
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