Interior lights on a Mainship 390

We have a 2002 Mainship 390 the ceiling lights are split 110V (6) and 12 V (4)and are all the same, they have a 10W G4 Bulb in them, It is my understanding the AC lights are stepped up through a transformer in the ceiling and connected to the AC Panel. If this is the case my question is can I replace the current AC Units with 12V DC LED Lights Reason for change is Chrome rings on existing lights are pitted, and I have changed the 12V lights already and would like all to match again. Many thanks

I replaced ALL lighting with LEDS, even nav lights and spreader lights. There is not 1 bulb that is not LED. My boat is 33 years old and for now kept the original fixtures.

Did that include 12Volt bulbs that are stepped up to AC on the AC Panel, many thanks

Yes. Not cheap but worth it.

I just replaced all my 10 W G4 lights (13) with 1.5W LEDs. I doubt yours are different voltages at the fixture our they wouldn’t be all the same bulb. Change one, the worst that can happen is you blow an LED. I bought a 20 pack off Amazon and they work great.

Inerior lights on a Mainship 390

I have a 2000 390. I converted all lights to the LED, and saw an immediate drop in current use, as well as less heat from lights.

Yes you are right, they are all 12v, and the 110v lights have transformers dropping down from the 110v to 12v.

Mainship did not leave alot of extra wire in the connections, so be careful when replacing fixtures that you can do a proper heat shrink connection with the short leads (I had 2 that were so short, it took 45 mins each to wiggle fingers in hole to make connections.) The others had enough length to make conversion to the new 12v fixtures easily. I had same problem with pitted chrome rings, so replaced each fixture with same design, but used white plastic housings...really update the look too.

Many thanks Suntan sounds like you did exactly what I am trying to do, changed all the 12 Volt fixtures to 12 Volt LED's and left the transformers alone I am going to use the Aqua Signal Chrome unit
I am trying to change the whole fixture (not just the bulbs0 to an LED fixture as the chrome rings are pitted on the existing Fixtures.
https://www.amazon.ca/gp/product/B001F6K710/ref=crt_ewc_img_srh_1?ie=UTF8&psc=1&smid=A3CSH382AQAXNC

I was also surprised that the bulbs in our lights controlled by a breaker on the AC side of the panel were the same as the bulbs on the DC controlled side. Then I found all the black transformers. All the light fixtures are the same with the same G4 bulbs. I replaced them all with LED's.

I replaced my halogen lights with LED. My bezels were pitted so I replaced the entire puck. I made no other changes. I monitored amp draw for each light circuit before and after the upgrade. The change is amazing.

The key is to spend money on the warmest light you can possibly get. Most inexpensive lights I found were very cold, making the light very blue.

I have heard how it was "pricey" to convert to LED. I just bought a 10 pack of G4 LED that replaces a 20W halogen. They cost $12.95. That's $1.30 a piece. I have only done the G4's as of now, so maybe there will be a more expensive bulb?

Also, I cant figure out how to open the 3 down lights in the salon! I have a 2006 Mainship 34T. There are no visible screws. I tried to twist them. I tried twisting the chrome and also, just the plastic lens. Has anyone opened these up?

By the way, by replacing all the interior and the 2 cockplt lights, 8 in total, the AMP draw was cut in half. From 10 AMPS to 5 AMPS. Once I change the last 3, it should be down to a 2 AMP draw.

Next, the spreader lights, anchor light and Nav lights.

Molly said:

I have heard how it was "pricey" to convert to LED. I just bought a 10 pack of G4 LED that replaces a 20W halogen. They cost $12.95. That's $1.30 a piece. I have only done the G4's as of now, so maybe there will be a more expensive bulb?

Also, I cant figure out how to open the 3 down lights in the salon! I have a 2006 Mainship 34T. There are no visible screws. I tried to twist them. I tried twisting the chrome and also, just the plastic lens. Has anyone opened these up?

By the way, by replacing all the interior and the 2 cockplt lights, 8 in total, the AMP draw was cut in half. From 10 AMPS to 5 AMPS. Once I change the last 3, it should be down to a 2 AMP draw.

Next, the spreader lights, anchor light and Nav lights.

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LEDs were expensive when they weren't so popular but for the most part they are reasonable now. I didn't bother with the nav lights since the engines are running anyway but did do the anchor light as well as all salon and cockpit lighting. On my G4 fixtures the bezel just pops off using a flat screwdriver. A picture of your fixture may help if that doesn't work.