Hacking into Factory Over Rear Lights?

[RememberTheFallen]

Sorry to start a new thread but wasn't having any luck when I asked in my pitiful build thread.

I have an 03 E350 passenger van that has three sets of factory overhead interior lights. Planning out my house battery and all of my electrical stuff and got to the lights. I want to be able to use the factory lights since they are already there. Problem is that they shut off after 10mins or so.

Is there any way to cut into the wiring harness to run those lights off the house battery and not have them shut off and be available all of the time? This may be a dumb question but I am still trying to grasp all of this electrical stuff without burning the van down. Figured one of you may have tried this on your lights.

Thanks for any help!



Joe

 

[boardrider247]

Joe,
You should have no problem intercepting the power and ground wires going to those lights and tapping them into your house battery system.
My assumption would be they are fed from somewhere in the front of the van. Should be as simple as clipping a couple wires and re splicing.
Obviously the existing power wire needs to be capped in some way so as not to cause you problems

Good luck
Danny

 

[RememberTheFallen]

Joe,
You should have no problem intercepting the power and ground wires going to those lights and tapping them into your house battery system.
My assumption would be they are fed from somewhere in the front of the van. Should be as simple as clipping a couple wires and re splicing.
Obviously the existing power wire needs to be capped in some way so as not to cause you problems

Good luck
Danny

Thanks Danny, I will pull the panels out and see what I can find.

 

[Vandit]

On my 2005 E350, all 3 overhead lights run on a single wire harness over to the B pillar behind the driver's seat. The lighting harness terminates into an actual plug which plugs into the van harness behind the plastic panel at the B pillar (towards the top). Since it terminates to a plug you should be able to test the wires fairly easily with a multimeter. I'm not sure if the '03's were any different, but it would certainly be worth a look. Hope this helps.

 

[RememberTheFallen]

On my 2005 E350, all 3 overhead lights run on a single wire harness over to the B pillar behind the driver's seat. The lighting harness terminates into an actual plug which plugs into the van harness behind the plastic panel at the B pillar (towards the top). Since it terminates to a plug you should be able to test the wires fairly easily with a multimeter. I'm not sure if the '03's were any different, but it would certainly be worth a look. Hope this helps.

Yes, it certainly does help! Thank you!

 

[Bikersmurf]

I'd hook up the lights with a couple of diodes so that they still would work with the factory harness, but you could override them with power from the house batteries. The pair of diodes would ensure that the house batteries would remain isolated from the starting battery.

Diodes only allow current to flow in one direction through them... (House +) -->-- (Light +) --<-- (Starting +)

Sorry for the crude diagram.

 

[boardrider247]

I'd hook up the lights with a couple of diodes so that they still would work with the factory harness, but you could override them with power from the house batteries. The pair of diodes would ensure that the house batteries would remain isolated from the starting battery.

Diodes only allow current to flow in one direction through them... (House +) -->-- (Light +) --<-- (Starting +)

Sorry for the crude diagram.

That is a great idea!

 

[RememberTheFallen]

I'd hook up the lights with a couple of diodes so that they still would work with the factory harness, but you could override them with power from the house batteries. The pair of diodes would ensure that the house batteries would remain isolated from the starting battery.

Diodes only allow current to flow in one direction through them... (House +) -->-- (Light +) --<-- (Starting +)

Sorry for the crude diagram.

I will look into that. May be too advanced for my simple electrical ability.

Never use the factor lights as is. The center bulb is even removed because I don't want the lights coming on every time I open the door. Not sure if I would need them to stay connected to the starting battery.