So I have a 2010 ford E150 that has some electrical issues that I can't seem to pin down. So I am not sure if I caused the problem but it all started after adding in a backup camera. I tied the back up camera on command into the hot wire of the driver side reverse light. It worked for a few months with no issues. The one rainy morning I went to put on my windshield wipers and they wouldn't come on. Then I went to back out of the drive way and the backup camera wouldn't come on. I set the e-brake and checked the rear and the back up lights where not coming on either. Not sure if the two are related or if I'm just lucky lol. I unhooked the camera just incase it was causing the issue. No dice. I have checked for continuity from the rear lamp to the plug under the dash and I have a good connection. But from the relay in the fuse box to that same plug it shows open. All fuses are good and I have 12v on pin 3 of the relay. I have tried jumping the relay and still get no voltage to the lights. I am thinking I have a broken connection in the fuse box its self? Has anyone had an issue like this? Is there anything else I should be checking?

 

First please check my signature below.
Then which head unit brand and model or your camera came with a dedicated display, which camera please send link. Find the install manual wiring of it please attach.
You said you hooked up the camera to the driver side reverse light, to get 12v from it or to energize a relay?
You mentioned about a relay in the fuse box, which exact relay? I need to know the relay number and its description.
You also mentioned you tried jumping a relay but still no voltage to the light, which relay?
You said you unhooked the camera, which part of it or entirely?

 

Wiring Diagram for your use...

 

It is a very inexpensive radio from amazon that comes with the camera. Like I said before it worked for awhile but now is not after that rain storm we had. Still not convinced they are related. The diagram that was shared by etinpa is the same diagram I was using for trouble shooting and that is the relay I am talking about. I hooked up the camera to the 12v of the backup light to give the radio the signal that I am backing up and to turn on the camera. When I disconnected the camera I disconnected the 12v wire to the backup lamp just incase the camera was causing a short. So if you look at his diagram he shared I was jumping pin 3 to pin 5 of the relay to transfer the 12v. I do have 12v on pin 3 of the relay. If I check for continuity from pin 5 of the relay to the connector C263 under the dash it measures open. The relay in question is #39 in the fuse box and it is a G8VA relay.

 

There's a splice (S142) between the fuse block and connector C263. That goes back to fuse F58 (see attached). You may want to check for power (or continuity) at that fuse.
S142 is on the cowl in front of the radiator.

I see from the instruction sheet you attached that there is also a connection for the reverse lamp circuit to the radio. Are you sure you didn't cause a break in the original wire when connecting that?

 

I will check that fuse and connector out. The reverse light connection at the radio connects to the other end of the video cable that runs back to the camera and ties into the 12v from the backup lamp that I was talking about.

 

It appears the wiper motor is within the SJB shown in red arrow above.
Supposedly you should obtain the 12V at splice S142 instead of C451 at the reverse lamp terminal 3.
The install manual diagram shows that you get the ground source from C451's terminal 1, that's a bad idea. The ground source, to avoid interference, should be obtained from another ground point other than G403.
You van already has a reverse lamp relay, so it's redundant to run another relay plus a diode unless you want to view the camera even when you are not in reverse.

You said there is no continuity between terminal 5 of the relay to C263 if that's the case then there is break somewhere in between. How about you run a jumper wire from terminal 5 to C263 directly?
Have you tried jumping terminal 3 (you confirmed 12v) directly to C263 and see if your reverse light is working or not?

Avoid using any type of connector that says "quick", use non-insulated butt splice + heat shrink tube instead.

 

Just to clarify I did not add any additional relays or diodes. If I am referencing a relay I am talking about one the vehicle already has. If I jump pin 5 of the backup light relay to connector C263. Can anyone verify if connector C263 is under the dash? I was assuming this was this connector because as I followed the wiring diagram from the taillights back it was the first connector I ran into. Today I took the wireloom apart that runs from under the dash all the way to the fuse box under the hood and can find no breaks. I am thinking more and more its my fuse box.

 

Yes, C263 is listed as being "under dash panel, LH side" in the service manual.

Here's the pin out for C263. You can compare the various wire colors and positions to confirm you're looking at the correct connector.

 

So now I am even more baffled. Like I said earlier I took all of the wire loom apart to find any breaks and did not. Frustrated after making my last post I went out side and put all the wire shielding back on and electrical taped it all back up. Now the backup lights and window wipers are working lol. So there has to be something up with that part of the wire harness. Anyone have an idea on if there is part of the wiring that the window wipers and backup lights share?