For voltage readings on a negative ground system, attach the black clip to ground and the red clip to whatever connector you need a voltage reading from, ignition switch, battery terminals, generator, lights, etc. The same pair of leads is used for checking point dwell, red lead to the distributor side of the coil, and black to ground. The same hookup is used for RPM readings- - - -push the high or low RPM button instead of "dwell". The "low volts/points" button is used for checking point resistance. With the ignition on and the points closed, with the red lead attached to the coil (-) terminal, the needle reading should be as close to zero as possible. Any measureable reading there indicates the points are dirty and need to be cleaned or replaced. A good set of points should indicate the same voltage as ground when closed. I'm not exactly sure what the "ignition output" button is for, never had much luck checking secondary ignition performance without an oscilloscope.
Jerry
Last edited by Hotrod Lincoln; 01/06/2014 4:24 AM.
