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Thread: MSD 6421 - 3 blinking status lights while turning over.

  1. #1

    Default MSD 6421 - 3 blinking status lights while turning over.

    I'm having a problem starting my car and I'd like to rule out whether the box is at fault or not. The car was running, but there was an issue with the turn signal. I’ve been having the same problem over the last two years when taking the car out of storage. It was running for a long while, however, when I turned it off and tried to start it would not turn over. Then the next day it would turn over, but no start. Status light will blink once when the key goes from off to accessory. Turn over will have 3 blinking lights (one per second) followed by a 3 second pause then 3 blinking light, etc. What can be done to troubleshoot this and if anyone knows what these lights are, it would be greatly appreciated. Thank you, George

  2. #2


    You can try doing the spark jump test to see if you can get a spark out of the coil wire.

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