Trillium 4500 wiring hookup

[Rick Norman]

Hi All,

I have just purchased a 1978 Trillium 4500 (bathroom model - VIN 1100892) and am having some issues getting the turn and brake lights to come on. The trailer has the standard 7 pin round plug and my car (Ford Escape) has the 4 pin flat connected to the rear lights, with a Reese 4 way to 7 way adapter in between. I've connected the two ends and grounded it to the frame of the trailer, but when activating the turn lights on the car the trailer lights do not come on.

Steps I have taken so far:

1) Verified that the connector on the car is working (hooked up another trailer directly from 4 pin to 4 pin and the lights work)
2) Confirmed that the connector on the trailer is working (hooked up a truck with a bulit-in 7 pin connector to the 7 pin plug on the trailer and everything works)

This tells me that everything at either end is working, and the issue is either with the adapter or the grounding. I tried a brand new 4 pin to 7 pin adapter and still no luck. I checked all the contacts and they seem fine; used a multimeter to check every pin on both the old and new adapter and everything is working.

Any help would be greatly appreciated. Looking forward to many years of use with the new (to me) toy, but until I can get the lights to work it is sitting on the seller's property :-(

[thrifty bill]

If your trailer has brakes, you will have to use a 7 pin connector. If not, you could swap out the seven pin connector on the trailer and install a four pin unit with a junction box.

I did just the opposite on mine, I removed the original four pin connector and installed a junction box with a seven pin connector. Parts cost me $20 on eBay. My trailer has no brakes. But my TV has a seven pin connector so I just made the change.

there is a wiring diagram for old Trilliums in the document center.

When I brought my Trillium home last year, I attached temporary trailer lights to it as about half the lights did not work. If the four plug connector on the trailer is original, I'd replace it first. I really like the J Box on my trailer A frame (came with the 7 wire setup). It made adding a battery much easier.

fullsizeoutput_e88 by wrk101, on Flickr

[Rick Norman]

Thanks. The trailer does not have brakes, nor does it have a battery, so I'm not sure why it even has 7 pin wiring. I do plan on adding a battery at some point, so maybe I should keep the existing wiring which I'm sure will be needed for this.
Good point about the temporary lights, this might be a good solution to get the trailer home so I could work on it more easily (I'm about 100 mi. away from where the trailer is currently sitting)
Appreciate the help so far, look forward to any more suggestions