Courtesy light power source?

OrioN

2008 2500 170" EXT
At a minimum, they feed/communicate with everything in the sliding door.

They may include the wires that would be used for the factory optional courtesy lights. Someone else will need to confirm this...
 

autostaretx

Erratic Member
Here's what the four wires to the sliding door do:

SlidingDoorCircuit.png

None are simple "power" and/or "ground".

The two that go to the lock motor are only driven when the door is asked to lock or unlock.
Their polarity *reverses* to accomplish the two different directs of travel.

The two coming from the switches are the "lock sense" and "door ajar" signal wires.
When the switches are closed (closed and locked), those inputs to the Control module are connected to one of the motor wires ... they wouldn't appreciate having a light confusing that.

That said, the motor wire they connect to *may* rest near "ground" most of the time.

There is no steady +12v in those wires. At best it would only be a momentary pulse as the lock transitions.

--dick
p.s. 2007 wiring diagrams:
http://diysprinter.co.uk/reference/07_Wiring-sprinter-2500.pdf (3rd party, above is Fig 48)
http://www.diysprinter.co.uk/reference/2007-sprinter-wiring-information.pdf (official MB)
 
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ptheland

2013 144" low top Passgr
They may include the wires that would be used for the factory optional courtesy lights. Someone else will need to confirm this...
My understanding is that Mercedes doesn't install a wire at the factory unless it's going to be used. So if the van never had the courtesy light in the step, it won't have a wire for it.

For the OP, I'd tap into the factory overhead dome lighting. Those are old-fashioned dumb lights, so they shouldn't mind an extra light attached to the circuit. Run the wires from over the door, down the b-pillar and right to where you need it. If you're really concerned about any extra load, use LED lighting. Those draw very little extra power, so they shouldn't cause any problem.

Plus the light will go on and off with the door opening, which should be a pretty good mode of operation.
 

autostaretx

Erratic Member
For the OP, I'd tap into the factory overhead dome lighting. Those are old-fashioned dumb lights, ....
Weeeelllll... there are (at least) two styles of dome lighting in the NCV3 ..

One is, indeed, old-school "dumb" (3 wires: power, ground, grey/brown heading off to the frame-mounted switch that will connect it to frame ground when the door is open).

The other is (too) smart "premium" lighting ... 4 wires to some of the lamps and capable of gradually dimming when turning off.

Figures 37 and 38 in here: http://diysprinter.co.uk/reference/07_Wiring-sprinter-2500.pdf

--dick
 

Sunny&75

Member
Weeeelllll... there are (at least) two styles of dome lighting in the NCV3 ..

One is, indeed, old-school "dumb" (3 wires: power, ground, grey/brown heading off to the frame-mounted switch that will connect it to frame ground when the door is open).

The other is (too) smart "premium" lighting ... 4 wires to some of the lamps and capable of gradually dimming when turning off.

Figures 37 and 38 in here: http://diysprinter.co.uk/reference/07_Wiring-sprinter-2500.pdf

--dick

My dome lights will turn off, after some time, when the door is open. I think I will splice into those. Was thinking of switching it as well in order to keep them on longer, but not sure how I can do that with this circuit?
 

Aqua Puttana

Poly - Thread Finder
Weeeelllll... there are (at least) two styles of dome lighting in the NCV3 ..

One is, indeed, old-school "dumb" (3 wires: power, ground, grey/brown heading off to the frame-mounted switch that will connect it to frame ground when the door is open).

The other is (too) smart "premium" lighting ... 4 wires to some of the lamps and capable of gradually dimming when turning off.

Figures 37 and 38 in here: http://diysprinter.co.uk/reference/07_Wiring-sprinter-2500.pdf

--dick
:thumbup:

Comments by others about the interior lights are that there is a constant 12 volt wire for the lights. There is not a solid ground wire (solid brown color). The dimming, etc. uses a conditioned signal on the negative/ground side.

It should be fairly straightforward to tap the interior light 12 volt constant wire and then use a frame ground for the added lights. I would put any switch for the added lights on the negative side as is done on typical door switched light circuits. Most door switch designs have a tap to ground included with the fastening screw.

:cheers: vic
 

Sunny&75

Member
:thumbup:

Comments by others about the interior lights are that there is a constant 12 volt wire for the lights. There is not a solid ground wire (solid brown color). The dimming, etc. uses a conditioned signal on the negative/ground side.

It should be fairly straightforward to tap the interior light 12 volt constant wire and then use a frame ground for the added lights. I would put any switch for the added lights on the negative side as is done on typical door switched light circuits. Most door switch designs have a tap to ground included with the fastening screw.

:cheers: vic
So, after playing with the stock interior lighting I've found that the dome light mounted at the rear switches on and off the other 2 lights in this circuit that are mounted to the ceiling. It is a 3 switch light, all off, all on, and auto where it turns on when a door is ajar. And stays on for 20 minutes according to the manual. Not great.
So, I would like to tap into this and add a switch at the opening of the sliding door. I would like to be able to turn these lights off at that location in less than 20 minutes. I'm adding this courtesy light at that same location by splicing in to that circuit at the ceiling.
How do I accomplish this?
 

OrioN

2008 2500 170" EXT
So, after playing with the stock interior lighting I've found that the dome light mounted at the rear switches on and off the other 2 lights in this circuit that are mounted to the ceiling. It is a 3 switch light, all off, all on, and auto where it turns on when a door is ajar. And stays on for 20 minutes according to the manual. Not great.
So, I would like to tap into this and add a switch at the opening of the sliding door. I would like to be able to turn these lights off at that location in less than 20 minutes. I'm adding this courtesy light at that same location by splicing in to that circuit at the ceiling.
How do I accomplish this?
I did a similar thing. I moved the switch from the rear door dome to the side door dome. In your case, considering that there will be enough cable after you pull it from the rear, you can mount the switch lower down and on the B-Pillar.
 
My understanding is that Mercedes doesn't install a wire at the factory unless it's going to be used. So if the van never had the courtesy light in the step, it won't have a wire for it.

For the OP, I'd tap into the factory overhead dome lighting. Those are old-fashioned dumb lights, so they shouldn't mind an extra light attached to the circuit. Run the wires from over the door, down the b-pillar and right to where you need it. If you're really concerned about any extra load, use LED lighting. Those draw very little extra power, so they shouldn't cause any problem.

Plus the light will go on and off with the door opening, which should be a pretty good mode of operation.
This is exactly what I had to do to add MB OEM door exit/puddle lights. Ran wires all the way up to the bulb in the overhead courtesy light as described. It's a shame they don't use a generic harness.

Best,
-Mark
 

autostaretx

Erratic Member
It's a shame they don't use a generic harness.
When you're making 60,000 vehicles per year, unused "wasted copper" can cost a lot of money.

--dick
 

warx

Member
I'm trying to re-use a two wire dome/courtesy light feed by the sliding door in a VS30. As mentioned above it's not a straight 12VDC or 0VDC feed even on the two wire taps. When "on" it is fine but when "off" my own LED light glows at about 1/4 brightness. . I guess I need to inspect the wires for each two states more closely. Or figure out what the OEM dome light is doing smartly. I really don't want to fit it in my new bamboo ceiling.
 

warx

Member
Ok, so
- "on" is 12V and with my Acegoo LED is 112ma (with nice fade on and off).
- "off" with glow is 7.6V and 2.5ma.
However, I noticed there is a third state when the ignition is off (or maybe has to be locked). It does shut off completely (0V - 0ma). It does a cycle though: hit lock: remains "on" - 30 secs. "off" - 20 secs. back on again but "soft glow" - 5 secs. Then off for good.

I have removed all three cargo area LED OEM domes and just have this acegoo LED and it does not seem to trigger a bulb failure (although reading other thread MB does not report interior bulb-outs anyways).

I'm going to leave it as-is. Even at 2.5ma if it turns on and I don't know about it it's not a big draw.
 

elemental

Dis member
The van sends a small amount of current through the circuit continuously. On the NCV3 vans with incandescent bulbs, the resistance of the bulb is enough to keep the bulb from visibly glowing, but people reported non-factory LEDs would sometimes illuminate. Putting a resistor in the circuit can stop the non-factory LEDs from lighting in this case. Perhaps the factory LED fixtures have some built-in resistance?
 

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