Umbilical Issue

[ALANSD]

Just installed A 4 PIN TO 7 pin plug for the 7 pin on my AS. The 4 pin is the standard on Ford Trucks from 2006. The blue brake power cord was there and I spliced it onto the blue 7 pin connector. I also grounded the white wire to the truck.

I have power in the 4 pin as tested. I seem to have power in the 7 pin part as my volt meter reads 12v across the connectors.

My umbilical will light up the trailer lights when a fuse is placed across the connectors while the trailer is on shore power.

BUT - I have no lights or brake connection when the umbilical is plugged into the truck end.

What the heck can this be? I opened up the trailer wire compartment and all is well. Cleaned the connections to be sure.

Cleaned all connection plates on the trailer umbilical with contact spray and a small screwdriver.

Help me troubleshoot this please!

[ALANSD]

Bought a set of portable trailer lights so at least I can to the AS to a hitch place,,,

[Melody Ranch]

The blue is notorious for being non standard. Be careful that your brakes don't apply when your lights are on. As a suggestion...just have the truck switched over to a seven pin system...like new and like all bigger trailers would use.

[Minno]

A four pin trailer connector does not have a brake wire. It should have ground, left tail/stop light, right tail/stop light, and running lights.

Back in 66, Airstream did not follow the current standard pin-out for the umbilical connector. You most likely have a miss-match on the pin-outs.

Here's a link to some wiring diagrams: Trailer Wiring Diagrams | etrailer.com

Good luck!
Chris

[55AS]

I had a similar problem. Ended up replacing the 7 pin cord end on the AS and spliced each wire after testing to ensure they matched the TV. You cannot go by the colors as they were non-standard back in the 60's.

[featherbedder]

Originally Posted by BambiTex

I had a similar problem. Ended up replacing the 7 pin cord end on the AS and spliced each wire after testing to ensure they matched the TV. You cannot go by the colors as they were non-standard back in the 60's.

Also 70s AS non standard wiring. Bill

[ALANSD]

got it and everything works. It was a bad ground. Had to drill a new hole and insert a screw for the ground wire to go onto. Many hours of frustration solved by a simple re-ground. AHHHH..now off to our rally.

[Secguru]

Caution! The 4-pin plug does not support trailer brakes. It cannot be configured to support trailer brakes. It does not have enough current carrying capacity to operate the brakes on an Airstream.

This is a disaster waiting for the first hard braking event.

[55AS]

Sounds like he found a brake power wire:
The blue brake power cord was there and I spliced it onto the blue 7 pin connector.

[ALANSD]

yes the blue cord was wrapped and right next to the 4 pin factory connector. The problem was the powder coated surfaces did not make for a good ground. Once I drilled thru,,well it all works now. The Expedition also had the brake controller connector ready to be plugged into. The harder part was finding a good spot to mount the Prodigy.

[55AS]

Cool.
My new F150 has an integrated brake controller from the factory. One less thing to add :-)