Electronics cut out when I turn on my spot light

[pdachsteiner]

When I turn on my spot light or cabin lights, my dual screen LCD's shut off. The spot light stay's on. I can turn the screens back on, but after a few seconds, they'll go out again. Sometimes when I trim my engines, the screens go out too, but not all the time. I have dual batteries that were recently replaced by a qualified mechanic. When I display the BATT gauge, it's show's over 13v, dips a little, but never goes lower than 12v. Any ideas where to start?

 

[alldodge]

Most likely there is to much load on the main feed to the electronics, and/or corrosion on ground and positive wiring.

You should have at least 10AWG wire Black and Red feeding the fuse panel and/or buss bars

Measure the output of the alternator and see if while the motor is at least 1500 rpm you see at least 14V

 

[pdachsteiner]

Thank you, that was the answer.

 

[mike_i]

Measure the voltage at the screen when you turn the spot light on. You may read good battery voltage on the dash gauge but you may have a bad/corroded connection causing low voltage going to the screens.