Start solenoid causing anchor light switch to arc?

[phil-b]

I just rewired my boat with a start switch for an electric start (Evinrude Fastwin) and was testing everything out.

My anchor/running lights switch is a two position pull switch (first position anchor, second position run+anchor). The anchor light is a multi-LED "bulb"

First I tested the lights, then twisted the key to start with the harness disconnected from the engine, and was happy to hear the start solenoid click. But when I release the key, I saw the anchor light flash, DESPITE the anchor/running lights switch being in the "off" position.

I’m guessing (with my meager understanding of electronics) I’m seeing "back EMF" from the solenoid.

To get a flash from the anchor light, I’m guessing the run/anchor switch is arcing (and maybe the start switch too)??

I imagine the "back EMF" is perfectly normal, and maybe visible because the LED lights with less current than a conventional bulb?

Anything to worry about?

My cheesy digital multimeter won’t give me a resistance reading for the anchor light.

[fleetwin]

Well, I surely am not in a position to comment on those terms you mentioned…
But, I will ask how your lights are wired. Are your lights wired directly to the battery using power and ground separate from the engine harness? The lights should not be sharing any of the engine harness circuitry. You could actually damage your coils by using the black wires in the engine harness for running light grounds. Isolate the light wiring from the engine harness, if it is not already and retest.
Finally, I would agree that the LED lights themselves might have something to do with this situation…

[crosbyman]

LEDs are funny… my CURT car/trailer module was "leaking" a few milliamps and kept my lights on all the time… I returned 4-5 units till Kia put in a Kia module … no more problems

a momentary flash is no big issue unless it leads to a "blow" LED … time will tell

if overly worried you could try a small (paper type non polarity sensitive) ) capacitor across the LED wires to absorb any kick backs from the selenoid

Joining AOMCI has priviledges 🙂

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