Trailer wiring issue cant seem to diagnose

[sublauxation]

Re: Trailer wiring issue cant seem to diagnose

Those testers aren't always accurate, just keep that in mind. A ground on both sides of the plug is a great start but you need to make sure the lights are also well grounded and that could potentially be missed depending on how he was reading voltage to the lights.

 

[briangcc]

Re: Trailer wiring issue cant seem to diagnose

I hate to state the obvious here BUT...there aren't separate fuses for L & R blinkers. At least, not on any of the vehicles I've ever owned....and that's Dodge, Nissan, Toyota, GM, and Pontiac (I list this separate as its a 78!).

Those trailer lights ground through the studs to the trailer frame right? IF so, do you have a GOOD ground connection there? I bet if you run a dedicated ground from your tow vehicle to the trouble light, your problems go away....which has been mentioned several times by many of the above posters.

 

[sublauxation]

Re: Trailer wiring issue cant seem to diagnose

I hate to state the obvious here BUT...there aren't separate fuses for L & R blinkers. At least, not on any of the vehicles I've ever owned....and that's Dodge, Nissan, Toyota, GM, and Pontiac (I list this separate as its a 78!).

Those trailer lights ground through the studs to the trailer frame right? IF so, do you have a GOOD ground connection there? I bet if you run a dedicated ground from your tow vehicle to the trouble light, your problems go away....which has been mentioned several times by many of the above posters.

Funny you left out Ford, my '04 Ford does! It took me a while to figure out that problem, but it didn't act like Tony's at all.

 

[briangcc]

Re: Trailer wiring issue cant seem to diagnose

Yeah but his tow vehicle works with the trailer disconnected so that rules out a fuse...unless there's a separate L&R fuse for his trailer lights.

Leave it to Ford to do something wonky with their electrical.

 

[UncleWillie]

Re: Trailer wiring issue cant seem to diagnose

There is a ground problem.

The problem is not the at the hitch because the Left, Right, and Tail lights would all be having issues.

Only the Right Light assemble is having the issue. That is where the ground issue is.
The bulb in the Tail Light is actually Two bulbs in one.
One filament is Brake/Turn signals combined.
The Other filament is the Tail lights.
They share the same ground.
The bulb has Three connections. Two Buttons on the Bottom; And the metal shell that makes up the base


With the tail lights only ON, the current will back feed through the Brake filament to find a ground, The tail Lights work slightly dimmed.
When the Brake lights come on, both wires have 12volts on them. there is no voltage differential, The tail light goes out.

With the tail lights ON measure from the side of the bulb to the trailer frame. Anything other than Zero is a problem. No Ground!

 

[sublauxation]

Re: Trailer wiring issue cant seem to diagnose

Yeah but his tow vehicle works with the trailer disconnected so that rules out a fuse...unless there's a separate L&R fuse for his trailer lights.

Leave it to Ford to do something wonky with their electrical.

...... That's why I laughed when I read your list that left out Ford:laugh:. His problem is certainly a ground or a bad light but my 04 Expedition does indeed have a separate fuse for L & R trailer lights. I never even considered that so I wasted an entire night tracing wires up towards the fuse box on the truck until I called a friend who said it was probably a fuse. I looked in the book and sure enough:joyous: there it was, trailer light fuses. Sometimes I hate electricity!

Another option....hook your trailer up to somebody's known working lights and see what happens. My guess is you'll get the same results.

 

[tonynoriega2]

Re: Trailer wiring issue cant seem to diagnose

 

[tonynoriega2]

Re: Trailer wiring issue cant seem to diagnose

Uncle,

Tried this with a basic voltage tester I got from Schucks, and with the alligator clipped to the frame, I touched the grounding component of the bulb on the right light, and it did not "light up" which, correct me if I am wrong, it would light up if there was current and not a proper ground...?

There is a ground problem.

The problem is not the at the hitch because the Left, Right, and Tail lights would all be having issues.

Only the Right Light assemble is having the issue. That is where the ground issue is.
The bulb in the Tail Light is actually Two bulbs in one.
One filament is Brake/Turn signals combined.
The Other filament is the Tail lights.
They share the same ground.
The bulb has Three connections. Two Buttons on the Bottom; And the metal shell that makes up the base
View attachment 200666

With the tail lights only ON, the current will back feed through the Brake filament to find a ground, The tail Lights work slightly dimmed.
When the Brake lights come on, both wires have 12volts on them. there is no voltage differential, The tail light goes out.

With the tail lights ON measure from the side of the bulb to the trailer frame. Anything other than Zero is a problem. No Ground!

 

[sublauxation]

Re: Trailer wiring issue cant seem to diagnose

Isn't electricity fun! Nice boat and video. If you can hook your trailer to a known working vehicle or your van to a known working trailer. I'd also dig through the owners's manual a little deeper and see if you can find a fuse for the trailer directional lights. Mine was mixed in with a couple other things that I never noticed weren't working until I found the blown fuse. On another Ford I did have a short in my vehicle's plug that acted pretty weird.

 

[1stgenbird]

Re: Trailer wiring issue cant seem to diagnose

I had a very similar issue last year and drove me nuts. Turns out it was caused by a couple of blown fuses under the hood of my Jeep Grand Cherokee. Took me quite a while to figure it out.

 

[ajax5240]

Re: Trailer wiring issue cant seem to diagnose

A blown fuse is a result of a problem, not the cause of one.

 

[Bondo]

Re: Trailer wiring issue cant seem to diagnose

Uncle,

Tried this with a basic voltage tester I got from Schucks, and with the alligator clipped to the frame, I touched the grounding component of the bulb on the right light, and it did not "light up" which, correct me if I am wrong, it would light up if there was current and not a proper ground...?

Ayuh,.... That would be a valid test, ONLY if the test light's ground lead is attached to the tow unit's negative battery post,.....

 

[tonynoriega2]

Re: Trailer wiring issue cant seem to diagnose

I did confirm that in a 1994 Ford Econoline 150 "Glaval" Conversion Van there is only one fuse that controls the "aux" components with a 7.5A fuse. It is still good, if it was blown, none of the trailer lights would be operating at all.

 

[Bondo]

Re: Trailer wiring issue cant seem to diagnose

I did confirm that in a 1994 Ford Econoline 150 "Glaval" Conversion Van there is only one fuse that controls the "aux" components with a 7.5A fuse. It is still good, if it was blown, none of the trailer lights would be operating at all.View attachment 200757

Ayuh,.... I believe you'll find that, that fusebox has Nothing to do with the wagon wirin',....

 

[batman99]

Re: Trailer wiring issue cant seem to diagnose

.

If this was my Boat Trailer giving me wiring problems, I'd:

Step 1:
- Connect known working trailer to your vehicle. Do full test.
- Connect your trailer to a different vehicle. Do full test.
- Does the problem stay with your vehicle or stay with your trailer?
This would be my first test.

2nd Test (assume problem with your trailer).
- Connect ground wire from your trailer frame to your Tow Vehicle's steel part. Thus, creating a sold frame ground.
- Using very long 12 gauge wire, connect Tow Vehicle's Pin directly to the Boat trailer light assembly. For example, remove existing wiring from back of each light and connect to this very long test wire. Thus, by-passing the trailer wiring. Test ALL light assembly lights this way. Does all individual lights work? If YES, then something is wrong with your trailer wiring (wiring hidden inside its frame tubes). If lights do NOT work, then problem inside the light assembly. re: Something isn't right within the light assembly and its "back feeding" the other light wire.

If testing your trailer lights is getting too dizzy / frustrating, simply draw a diagram. Confirm all wire colors by doing a current flow test with a 12V probe tester, Simply draw a diagram for each light and remember frame ground must be grounded to Tow Vehicle as well. For a good picture, surf: http://rv-mobile-services.ca/wp-content/uploads/2011/10/wiredtrailer.jpg

Note: If I cannot find the cause of a wiring problem on my trailer, I simply "remove" its existing old wiring and re-wire from scratch. I use PEX tubing outside the trailer's frame and use thicker 12 gauge wiring as well. And use 10 gauge STAR wiring design for its electric brakes. Install new wiring from scratch using diagram http://rv-mobile-services.ca/wp-content/uploads/2011/10/wiredtrailer.jpg Thus, eliminating any hidden wire shorts inside the steel frame as well.

Hope this helps.

 

[UncleWillie]

Re: Trailer wiring issue cant seem to diagnose

With the trailer unplugged , and using your test light ....
Turn ON the Tail Lights, AND the 4 way Emergency Flashers.

Attach the Test light Ground to Pin #1 of the 7 to 4 pin adapter.
Touch each of the other pins.

Pin #1 Ground, White, (Bottom Pin in your case).
Pin #2 Tail Lights, Brown, Test Light ON Solid.
Pin #3 Left Brake/Turn, Yellow, Test Light Flashes.
Pin #4 Right Brake/Turn, Green, Test Light Flashes.

If this works as expected, follow and test the Green wire until the test light stops flashing.
If this doesn't check out, the problem is in the Adapter or the Truck.

Note: Sanding the hitch, Receiver, and Ball mount has NOTHING to do with the problem.
You can take the trailer off the ball, remove the chains and attach ONLY the 4 pin Plug, and the lights will work.

 

[sweet addiction]

Re: Trailer wiring issue cant seem to diagnose

90% of all trailer light/wiring issues stem from a bad ground on the trailer and/or the tow vehicle as well as corrosion in a light fixture on the trailer. Dielectric grease is your best friend.

 

[tonynoriega2]

Re: Trailer wiring issue cant seem to diagnose

Thanks guys... the girls are leaving for most of the day and ill try these next steps. Thanks for the advice, Ill be back with a report and analysis of what I found soon.

 

[tonynoriega2]

Re: Trailer wiring issue cant seem to diagnose

Ok, so the verdict is in. Hooked up my buddies truck last night, plugged into his 4 flat , and the lights worked perfect.

Its the van.

 

[colbyt]

Re: Trailer wiring issue cant seem to diagnose

Ok, so the verdict is in. Hooked up my buddies truck last night, plugged into his 4 flat , and the lights worked perfect.

Its the van.

I refer you to post number 3.


Edit: The Hopkins catalog http://www.hopkinsmfg.com/catalog/HTSCatalog.pdf

page 54 says the 40315 kit fits your 1994 van

That leads me to believe that you must have an inverter / converter on the truck somewhere.