moxnix Reader
April 26, 2013 7:47 a.m.

2006 ford E-350 Every time I shift the van into reverse the trailer backup/running lights fuse blows.

It does this when the trailer is hooked up and when it is unhooked so it is not the trailer.

The van backup lights work fine.

Fuse is fuse 24 under the hood (Trailer tow running lamps and back-up lamp relays) Are there any known issues or where should I start troubleshooting on this? (I dislike wiring issues)

mad_machine MegaDork
April 26, 2013 7:49 a.m.

I don;t know of any known issues.. but I would start with the switch that controls your reverse lights and work your way back.

wae Reader
April 26, 2013 8:13 a.m.

I had the same problem on my way to the $2011 Challenge in my '06 E-150. I pulled the "Trailer Backup Lamps Relay" out of the PDC under the hood and all my problems were solved.

I've had the relay sitting here on my desk at work ever since I got back from the Challenge that year and one of these days, I swear I'm going to test it to see if the relay is bad. Some day. I gave the wiring a quick look and didn't see anything that looked like it would be shorting out, and it happened with or without the trailer hooked up, so I know the problem is on board the van somewhere. Since everything works without that relay and my trailer doesn't have any reverse lights or a surge brake that needs to be defeated, I haven't been all that motivated to find out exactly what's going on.

iceracer UberDork
April 26, 2013 9:53 a.m.

check the trailer wiring.

wvumtnbkr HalfDork
April 26, 2013 10:19 a.m.

Don't back up.

wbjones PowerDork
April 26, 2013 12:05 p.m.
iceracer wrote: check the trailer wiring.

he said it did the same thing whether the trailer was hooked up on not

1988RedT2 UberDork
April 26, 2013 12:15 p.m.
wvumtnbkr wrote: Don't back up.


Stop me if you've heard this one:

A man goes to the doctor. "Doc, it hurts whenever I do this!" Doc says "Don't do that!"

‘Doctor, doctor, I think I’m suffering from déjà vu!’ ‘Hang on! Didn’t I see you yesterday?’

‘Doctor, doctor, I think I’m a dog.’ ‘How long have you felt like this?’ ‘Ever since I was a puppy!’

‘Doctor, doctor, I think I’m a bridge.’ ‘What’s come over you?’ ‘Two cars, a truck, and a coach.’

‘Doctor, doctor, I think I need glasses.’ ‘You certainly do. This is a garage.’

‘Doctor, doctor, I keep thinking I’m invisible.’ ‘Who the hell said that?’

moxnix Reader
April 26, 2013 1:41 p.m.
wae wrote: I had the same problem on my way to the $2011 Challenge in my '06 E-150. I pulled the "Trailer Backup Lamps Relay" out of the PDC under the hood and all my problems were solved.

Thanks. Just tried that and that will at least stop me from blowing fuses until I figure it out since I have electric brakes and I can live without backup lights on the trailer if it even has them.

I swapped the Trailer backup relay with the running light relay right beside it (same part number) and the fuse still blew so looks like it is not the relay.

I have been trying the don't back up method and it works about as well as the rhythm method.

So I guess it is isolated to van wiring past the relay

wae Reader
April 26, 2013 1:49 p.m.

Well, I guess you saved me from having to get around to testing this relay :)

Honestly, the only thing that I've ever personally seen the backup light power connection do for a trailer is to defeat the surge brakes so that you can reverse a trailer equipped with them. If you're motivated enough to try to actually fix the problem, I'd probably start in the connector under the bumper. I hear those are prone to being invaded by water and getting corroded and shorted out.

iceracer UberDork
April 26, 2013 5:17 p.m.
wbjones wrote:
iceracer wrote: check the trailer wiring.

he said it did the same thing whether the trailer was hooked up on not

Yeah I got confused with trailers and backup lights.

You'll need to log in to post.

Also on Grassroots Motorsports

From the GRM Vault: The Art of Understatement

1 day ago in Articles

The Harvey brothers dominated autocross in an obsolete Datsun a couple decades ago.

2017 Volkswagen Golf TSI SE

1 day ago in New Car Reviews

The quintessential European hatchback continues to pour out of Volkswagen's plants. Our test car featured four doors, a turbocharged 4-cylinder ...

Join the Grassroots Motorsports Dyno Day

2 days ago in News

Join us for a dyno day in Sterling, Virginia.

We're Giving Away a $500 Race Ramps Certificate

2 days ago in News

Joining the drawing is totally free.

25 Project Path

3 days ago in Articles

A walk through 25 of our favorite project cars from the past.

Our Turbo Miata Goes Boom

3 days ago in Project Cars

Engine swap and suspension revamp before our race in two weeks? Challenge accepted.

The Ultimate Weekend Getaway for Your Car Club

4 days ago in News

Save a corral space just for your club at the Mitty.

Reader's Ride of the Week: V8 Jag

4 days ago in News

It’s a long-wheelbase 1974 Jaguar XJ6 fitted with a 350-cubic-inch Chevy V8.

Honing Cylinders

4 days ago in Project Cars

We hone our LS1's cylinders

Break Maiden

1 week ago in Articles

Creating a turbocharged road racing champion from a vintage Ford Mustang.

Meet Us at Sebring

1 week ago in News

We'll be at the Mobil 1 Twelve Hours of Sebring. Will you?

2017 Honda Accord Coupe Touring

1 week ago in New Car Reviews

Honda has been pumping out Accords for over 40 years now. Obviously they have a recipe that just plain works. ...


Grassroots Motorsports Magazine

Subscribe Today

Also get your instant access to the digital edition of Grassroots Motorsports Magazine!

Learn More