On Sat, 9 Jun 2012 11:13:10 -0700 (PDT), spamtrap1888
wrote:

I have memorized this rule of thumb as "Two wrongs don't make a right,
but three rights make a left."

Correct. Three ultra right wing politicians have the same effect as
one left wing politician.

Sure. *Clean contacts and connections (steering column switch, bulb
connectors, flasher connector, relay). *Replace everything (bulbs,
relay, and flasher). *Whatever you do last, is usually what fixes the
problem. *My wild guess would be a flasher relay as in:

But the flasher relay works on the left turn signal.

Yep and until we ascertain what manner of vehicle we're dealing with,
it's difficult to determine how it's wired and what might be wrong.
I'll pass instead of guess.

Turn signal wiring diagrams:
https://www.google.com/search?q=turn+signal+wiring+diagram+relay&tbm=isch
Note that most vehicles have TWO turn signal relays and sometimes TWO
thermal flashers:
http://www.mg-tabc.org/techn-up/turn_signal_relay/turnsignalrelay.html
http://www.dezertrangers.com/vb/attachments/general-off-road-talk/136623d1202261254-turn-signal-relay-diagram.jpg

I believe the flasher doesn't switch on the right because the load
draws more current than it should, indicating most likely that the
wrong bulb(s) were used or that somehow there is a current path
parallel to the bulb. First I would take out each bulb, checking to
see if the other flashes. (The open circuit should result in high
speed flashing, then reseat the bulbs and try again. Make a note of
the bulb numbers and check against owner's manual.

In my limited experience, an open circuit usually results in no lights
flashing because there is no circuit between the flasher and the
bulbs. However, if one of the two bulbs involved was blown, the
remaining light will light and not flash, while the blow light will
ummm... act like a blown light and not light. In this case, both
lights are lit, which makes a bulb failure unlikely.

IIRC, when we used to go trailering we had to put a heavier duty
signal-stat into our car, to switch the increased load of the parallel
trailer turn signal lights. Otherwise they would just light up.

That's a likely possibility. However, my crystal ball and Ouija Board
both concur that the most likely culprit is an arced shut relay.
Hopefully, when the OP returns, we can determine whether your logic
and experience will triumph over my guesswork and magic.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558