12 v socket and spot light

[pwmullins]

Have a 42 sail and for several years have had a 12 v socket mounted at the steering binacle to insert a 12v fan plug or a spot light plug. Finally rusted out and disposed of the 12 v spot light. Wired it to the ignition switch post, a black and a red. Worked perfectly for years.

New socket, wired the same way and bought a new 12 v. spot from West Marine. When I plug the 12 v fan in , it works perfect.

When I plug the spot light in, and turn it on, the engine starts....crazy!!!!

I've tried to change the wiring on the ignition switch, but it doesn't help, it just turns on the oil alarm. Any ideas?

[Reefmagnet]

Your socket likely isn't wired properly. Check the voltage between the socket negative and the battery negative and same again for the positive wire to battery positive with the light (or another device, even) plugged into the socket and powered on. If you notice more than say a volt or so on the meter, that indicates a problem with that wire in the circuit.

[leftbrainstuff]

Originally Posted by pwmullins

Have a 42 sail and for several years have had a 12 v socket mounted at the steering binacle to insert a 12v fan plug or a spot light plug. Finally rusted out and disposed of the 12 v spot light. Wired it to the ignition switch post, a black and a red. Worked perfectly for years.

New socket, wired the same way and bought a new 12 v. spot from West Marine. When I plug the 12 v fan in , it works perfect.

When I plug the spot light in, and turn it on, the engine starts....crazy!!!!

I've tried to change the wiring on the ignition switch, but it doesn't help, it just turns on the oil alarm. Any ideas?

Trace the wiring to see if its how you think it should be. Has someone crimped another load just because it was easy to reach?

It's 12V DC so you should have positive at the pin and negative at the barrel.

Have you checked the polarity on the fan and spotlight to see if they are the same?

Is there another circuit, switch or load connected in this circuit?

Dont add anything. Back to basics. Isolated circuits are preferred.

Sent from my SM-N900T using Cruisers Sailing Forum mobile app

[Wotname]

^^ what RM & LBS said +1.
Plus I'm betting your new spot light has a significantly higher power rating than the old one
Plus either your +ve or -ve on the socket actually goes to another load and always did but never caused a problem due to only ever having to supply a small load like the fan or old spotlight.

[jkindredpdx]

... did you connect the plug red to red on the starter switch and black to black? What if you connect your plug black wire to a neg bar instead.

[OS2Dude]

Why wire it to the ignition? I pulled a new wire for my cockpit 12vt plug.

The ignition switch completes a circuit, as I would think your new light does. The old light and fan likely do not pass enough juice to start the engine, but it seems like the new one does.

Pull a new 12vt wire from the battery or a common connection point. Don't cut corners and wire into a in existing circuit, unless you already have a 12vt plug circuit in the cabin.

[markpierce]

That's weird. I've got a twelve-volt outlet at the helm and the saloon's desk. They've never started the engine. Doubt that's because the majority of the boat's DC electric is 24-volt. ... Sounds like you've got amateur wiring. May I suggest you employ an expert electrician?