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Check to make sure you have Ignition Voltage at the RED/BLUE wire of the ignition module - if OK, then hook a test lamp with Clamp end to Battery POWER and put the shaft tip on the GROUND side of the coil - while cranking, see if the test lamp 'pulse flashes'. Let me know. Thanks, Dave.
Don't put the clamp of the test lamp to the coil positive, put it to the BATTERY positive. Yes, RED/BLUE is CRANKING voltage and the constant voltage comes from the the BLUE wire. Having voltage on both sides of the coil at rest is normal (it is a continuous winding) - when the module picks up a trigger from the pick up magnet inside the distributor, it sends a ground trigger to the coil negative side to fire it - this is why your test lamp should flash when the ground pulse occurs. Make sure you have the voltage at the BLUE wire of the ignition module. I am not showing a WHITE wire at the MODULE - I show the colors as ORANGE/YELLOW, BLACK/GREEN, PURPLE/BLUE, GREEN/YELLOW, RED/BLUE and BLUE to RED/YELLOW. Thanks, Dave.
No, just disconnect it from the ground side of the coil and disconnect the plug at the modulator - then connect an OHM meter to the GREEN/YELLOW at both ends and make sure the circuit has some resistance - it is just to check that the circuit is not OPEN (broken wire). Thanks, Dave.