Passenger Side Fuse Blowing E 350 2007

patrick51 · 10-08-2016, 10:32 AM

Had this van since new, and suddenly int/ext lights are out and I can't keep fuses from blowing. any thoughts on troubleshooting? I have LED's bulbs, so unsure if thats where to start?

**daveb** · 10-08-2016, 02:19 PM

Try whatever is the easiest first. Divide or disconnect each circuit run and test if you don't see something obvious. Look over each light fixture if possible. Maybe it's as simple as a butt connector that pulled apart.

Can you do an amp check and see what the trip threshold is? You say "suddenly". Have you done anything out of the normal lately?
I had a similar problem with my backup light circuit. The lights themselves tested good as did the backup sensors tied to the same circuit. In the end I had to run a brand new circuit and abandon the old one. Never did find the cause...lots of sharp metal for wires to short.

Good luck on your repairs.

Flux · 10-08-2016, 02:43 PM

Aftermarket LEDs??

patrick51 · 10-08-2016, 03:01 PM

I have the original 07 seperator and think its the problem,somehow letting high amps through the fuse block. By disconnecting the ground I was hearing it conn/disconn. Other than that I have not heard it operating

**daveb** · 10-08-2016, 03:23 PM

Quote:

Originally Posted by patrick51

I have the original 07 seperator and think its the problem,somehow letting high amps through the fuse block. By disconnecting the ground I was hearing it conn/disconn. Other than that I have not heard it operating

I doubt it's a separator problem causing the fuse to blow unless that circuit feeds the separators electronics. In 07 they were still using the Surepower if not mistaken and pulling the ground makes the unit open. Where is the fuse blowing? Is it at the SMB fuse block? Most builds have a larger bus wire that runs to the SMB fuse block and from that block each fuse supplies power to one or more circuits. There usually a larger (like 40 amp) breaker before the fuse block to protect it. If that is out you'd have a lot more than just lights out. It's hard to trace wires that run through tight quarters. My fuse block is under the rear bed/seat. Wire runs distribute from there and go to different section on the van. Sometimes starting at the source is difficult and you'd hate to do a bunch of work ripping stuff out when in the end you might find a bad light socket, or short that can be found by inspection.

patrick51 · 10-08-2016, 03:28 PM

Yes, the fuse is 30amp and blowing in the underseat block. It is listed as the passenger side fuse. I have high power somehow getting into that circuit as when I attempt to put in a fuse, the power is just melting the tangs on the fuse!

patrick51 · 10-08-2016, 03:29 PM

You suggest checking the light sockets, how? Multimeter?

**daveb** · 10-08-2016, 03:57 PM

Visually, looking for loose or pinched wires, or bad sockets. You might first pull all the bulbs and try to install the fuse to see if it blows. I had my bed/seat mechanism pinch one run that caused a similar issue. Make sure the fuse block also looks sound... no melted stuff.

**daveb** · 10-08-2016, 04:01 PM

BTW 30 amps is way big for just lights. Does it also feed something else besides the lights? Maybe a 12v power outlet or two? Those can short easy or rattle loose.

Scalf77 · 10-08-2016, 04:02 PM

On the distribution side of the fuse (side the wire comes out of) with fuse out of course, ohm out to ground. If it reads shorted, that would be causes the fuse to blow. It could be any of the lights on passenger side, possibly water pump depending on build (although it has its own fuse), also any 12 volt power circuits on that side for sure would come off of that. What kind of layout do you have? If you can switch off anything that you know is tied to that fuse and the issue goes away the problem is downstream of that.

-greg