2000 Mercruiser MCM 5.0L Alpha with Denso 131800-7071 ignition module. There is absolutely no spark from the coil when cranking.
But here is a clue, although I don't know exactly what it means: There are two wires running from the distributor ignition sensor to the Denso module, WHT/RED & WHT/GRN. I disconnected them both and used my 12 V test light to check for presence of 12 V coming from the module on either one. As soon as I touched the grounded test light to one (I forget which) there was a nice 1" blue spark from the coil wire to the engine block.
I'm wondering how to determine if I have a bad ignition sensor or bad ignition module. I'm thinking it's the sensor since bypassing it produced a spark. Can I use an ohmmeter to check the sensor while cranking as if there were points?
Thanks for your expert help!
But here is a clue, although I don't know exactly what it means: There are two wires running from the distributor ignition sensor to the Denso module, WHT/RED & WHT/GRN. I disconnected them both and used my 12 V test light to check for presence of 12 V coming from the module on either one. As soon as I touched the grounded test light to one (I forget which) there was a nice 1" blue spark from the coil wire to the engine block.
I'm wondering how to determine if I have a bad ignition sensor or bad ignition module. I'm thinking it's the sensor since bypassing it produced a spark. Can I use an ohmmeter to check the sensor while cranking as if there were points?
Thanks for your expert help!