Battery Source Test

Without disconnecting coil, connect voltmeter between coil BAT terminal and engine ground. Connect a jumper wire from coil DEC terminal to a good ground. Turn all lights and accessories off and ignition on. A voltmeter reading between 4.9 and 7.9 volts indicates primary circuit from battery to coil is satisfactory. If reading is less than 4.9 volts, inspect primary wiring and resistance wire for worn insulation, broken strands and loose or corroded terminals. If reading is greater than 7.9 volts, check and replace resistance wire as necessary.