Ed,

You need a converter.  There are powered ones and nonpowered ones
(parasitic).  The powered ones don't put a load the van's taillights to
run the trailer's lights.  Obviously, the powered ones will cost more.

Nonpowered run for around $15.00 and powered for about $40 or $50.

When you're shopping, look for ones designed for vehicles with amber
turn signals (turn signals that aren't part of the stoplights).

I use a powered one, a TAP 970, but there are others.  A TAP 970 can be
seen at http://www.racersrvstuff.com/racersrv/details.php?ITEM=3209000
but I did not get mine here.  I just googled and this site is one of the
hits.

I hope this helps.

Mike

Ed Wiebe wrote:
> I'm purchasing a trailer to tow with the van.  The trailer has a 4 wire inline plug labelled: white=ground, Brown= taillights, Yellow= left turn and stop, Green= right turn and stop.
> In other words the turn signals and brake lights are on a shared connection.
> The Westie has separate wires for each turn signal and the brake light, which means a 5 wire connection.
> The question is: Do I have to change the trailer lights, or is there a way to hook up this combination.
> Thanks in advance.  I don't post very often but am a faithful reader and learn a lot from all you experts.
>
> Ed Wiebe
>