We are currently in the middle of converting our 2017 4×4 Sprinter from a passenger van into a camper and it’s time to choose the lighting that will be installed in our custom built ceiling panels. On the recommendation of a friend we decided to use Genuine Marine low profile LED lights. These lights have some great features and are reasonably priced, plus they are easy on your battery as they only draw 3W each or .23 amps at 13V.
Dual Position Switch/Switches (DPDT): Available on Amazon
Marine heat shrink connectors: Available on Amazon
Heat shrink connector crimp tool: Available on Amazon
Brother E550W Heat Shrink Label Maker: Available on Amazon
The 6 lights arrive well packed in this cool little round case. I’m sure this case will come in handy for something down the road
Here’s one of the lights as it came out of the package. Parts consist of the light unit itself, the trim ring and the screws to attach the light to the ceiling panel. The center metal ring is where you touch the light to control it’s on/off/dim functions.
To mount the light to the ceiling you drill a small hole for the wiring to pass through then slip the wiring up into the ceiling. NOTE: I’ll be removing the ceiling panel after the lights are installed to finish up the wiring, if you are replacing an existing light you would connect the light to the vans wiring at this point. Also note that the edges of the tweed are burnt with a soldering iron where the hole was drilled to keep the fabric from fraying over time.
Next attach the light unit to the ceiling panel with the provided screws. Sorry for the blurry pic here.
All that’s left is to snap the trim ring into place and your done with the physical install portion, piece of cake! More on the switch assembly next.
Switches, Wiring…….and Options!
I love options so I’m always looking for ways to maximize usability when installing accessories. When I installed the lights I decided to add dual position switches into the circuits to allow for dual power options for each set of lights. Each switch will control 2 lights, 3 switches total (Front, Middle and Rear). The lights themselves are touch sensitive and can be turned on/off individually and have a built in memory so they will start back up in their last used mode of operation. The combination of the switches in the circuit and the on/off/memory functionality built into the lights provide for a large number of available lighting options depending on your needs at the time. (Video showing these options in action at the end of this article)
The lights will function as follows:
*Switch in position I: Lights will be powered from the factory dome light circuit and function with the door switches as would the factory dome lights. In this position lights are powered from the starting battery.
*Switch in Position O: Lights are manually turned off
*Switch in Position II: Lights are in manual mode and powered from the Aux battery. This is the mode that will be utilized when parked or camping.
In either Mode I or II you can additionally control each light at the light itself, turning them on or off and dimming each individual light as needed.
Note on wiring lights to the factory dome light circuits: The Sprinter uses a SAM (Signal Acquisition Module) that processes the signals from the door switches and ultimately controls the dome lights. This is basically a small computer circuit and it can be sensitive to changes in loads or resistance. The module controls the dome lights by controlling the ground circuit instead of the powered circuit like most vehicles. Care needs to be taken when hooking lights up to the factory wiring as if the loads are to little or to great the computer can get freaked out and shut the circuit down requiring the system to be reset to function again. My friend has installed these lights in several sprinters and hasn’t had any issues with the SAM modules so far. My lights are working great so far as well. 👍 Just a note worth mentioning and being aware of.
Here’s a close up look at the switch assemblies that I will be using.
Next up I needed to fabricate some aluminum backing plates that will allow me to attach the switches to my ceiling panels. You can purchase these backing plates pre made and power coated but I was in a hurry to assemble eveything so decided to fabricate my own. Here’s a link to the pre-made units: CLICK HERE
I’ll post pictures of the process I used to fabricate my backing plates for reference in case anyone wants to create their own.
Aluminum plate sheered to size and clamped in the vice, I have the outline of the required cutout drawn onto the aluminum in black sharpie.
Using a drill I made 4 holes on the inside of the cut out area, the holes are big enough to allow the jig saw blade to fit through.
Next I used the jig saw to cut out the center portion until I had a square hole.
Now I used a washer to mark the corners and a disk sander to round the corners off.
Edges brushed up with a file, mounting holes drilled and a couple coats of textured black paint……ready for install!
All three units assembled. Also shown here is the power ports I’ll be installing later to power my portable fridge.
Here’s a diagram showing how to wire the Double Throw Double Poll switch assemblies to operate from two different power sources.
With the ceiling panels removed and in the shop it’s time to wire up the lights. Here I’m pressing some rubber grommets down into the hole through the wood panel to keep the wiring from rubbing against the sharp edged of the wood. Nice and snug!
Electrical Connectors: I prefer to use marine grade electrical crimps on all my builds. These connectors utilize heat shrink with a glue inside and once properly assembled they are waterproof and hold extremely well! One note is that you need a special heat shrink electrical crimper to crimp these connectors without damaging the heat shrink layer. The tools are very affordable and well worth having in your tool kit! (Link to crimper at the top of the page).
Here I’m joining the LED light to some wire with a butt connector to make a wire harness .
Now just hit the connector with a heat gun and you have a reliable electrical connection.
Another thing I always do on my projects is label all the wiring with printed heat shrink tubing. The extra effort up front pays for itself down the road when your trouble shooting, removing/re-installing panels etc. The costs of labeling machines have come way down in recent years and they are now very affordable. I’m using the Brother PT-E550W Label Machine (link at the top). This unit works great and there are plenty of generic cartridges available on eBay for about $10 per cartridge. The heat shrink is available in many different sizes and as a bonus you can make standard labels as well. On a side note you don’t need to spend the $$ on a label maker if your only doing one project, just take a piece of tape and make a flag on the end of the wire then mark it with a sharpie pen 👍.
Lights connected to the switch. Note the lights are wired in parallel.
Some plastic loom added to the wiring. Note: I used sticky anchors to attach the loom to the panels, the tape on these fail quickly so this really only helps for install and really wasn’t needed.
Factory Dome light wiring: Red is constant pwr, Brown/Blue is switched ground. Starting battery was getting low in this shot, right after this pic I hooked up the portable solar panel to top off the battery.
Factory connector removed from the dome light wiring and new connectors crimped in place.
Aux battery power: I ran pre-tinned marine wire for this run that will power both the lights and my two Maxxfan roof fan units. The lights use less than .23 amps each and my two fans are 3.7amps each, 14awg is plenty good here for this length of wire run.
Almost ready to re-install the panels, lots of wiring.
Ceiling panels back in place.
Lights powered up! The lights provide a nice warm tone.
Here’s a video showing the functionality of the lights and the switches in action.
Overall impression? I love these lights! These lights work and look great and I would highly recommend them if your looking for low profile LED lights. My one and only gripe is I wish I could dim them a little more then they allow, but it’s really not a huge issue. 6 of these lights provide a LOT of light!