If you have problems locating the trailer relay locally they carry them at Summit and Summit ships quickly.

Good, Bad, and Crappy Converters
 

I read some of the Amazon reviews of some of the cheaper 3 to 2 converters and some of the guys there complain of the huge voltage drop in them (which makes your lights dim). This one claims to be "heavy duty" and to put out six whole amps of current. Who knows. If Bliss is lucky, it'll just turn out to be a bad connection or almost-broken wire.

[ame="http://www.amazon.com/Trailer-Heavy-Duty-Taillight-Converter-5423203/dp/B00MJUPD60/ref=sr_1_1?ie=UTF8&qid=1412129305&sr=8-1&keywords=stag+trailer+converter+3+to+2+heavy+duty"]Amazon.com: RV Trailer Camper Heavy-Duty 3-2 Solid State Taillight Converter 5423203: Automotive@@AMEPARAM@@http://ecx.images-amazon.com/images/I/41F17OWUw8L.@@AMEPARAM@@41F17OWUw8L[/ame]

I ordered a cheap one from eBay. At this point, I don't know if my unit is OK or not - need a backup just in case.

Question: Front signal lights - they work fine as noted above, but I somehow blow one while fooling with the wiring - the ERA parts list states it's a 1157, same at the rear lights. Well, it isn't on my Cobra - it's a Lucas 189 which, of course, no one has in this area. Anyway, do you happen to know what the equivalent is or do I need to find this exact product?

I think a Lucas 189 is the same as an 1176. At least that's what Don's Light Bulb page says.... dons bulbs - light bulbs If it has the same base size, and the same number of filaments, and kind of looks the same, then I think it'll be ok.

At one time, the front twist-off lights were coming through with sockets for even-height pins. That's where 1176 bulbs were required. Since the bulb can be inserted "backwards", you must check that the parking lights are on the less-bright filament. Otherwise, turn them 180 degrees in the socket.

The 1176 works just fine, thanks.

Hurray. Now the only other things you need to diagnose the problem are a simple $10 Volt Meter from Lowes, Radio Shack, or the like, and a nice long piece of wire, say about ten feet long, with the thickness of a typical lamp cord, and put alligator clips on both ends of it.

All we will be doing is to first get the signal working, and then we'll do a voltage drop check along both sides of the circuit. This is very easy to do and, for anyone else that reads this thread, it will be an insight in to how to diagnose a misbehaving circuit by measuring voltage drop (both on the hot side of the circuit and on the ground side of the circuit).

Your First Step...
 

I disconnected my trailer relay and measured the voltages, drops, and tested it along the signal/brake light circuit, both while it was operational and while it was apart. (This was not a big a job, it took about ten minutes.) I also tested it using a really simple 12v test light, since it's almost impossible to hurt anything on a car's circuit using a test light -- so that's what I'm going to recommend you start with.;)

So, your first step to fix the circuit is to carefully cut back the insulation from the green and yellow wires that come off of the "trailer side" of the trailer relay (not the "car side" of the trailer relay that also has the red wire going in to it). Do not cut the wires in two, just shave the insulation off of them. Then, with those two wires exposed, attach your 12v test light to a good ground and then to each wire, one at a time. Test your brakes and turn signals with the light attached to each wire. See if the test light behaves correctly or if it misbehaves like your car's lights do. Put it through all the paces by testing it with other lights, like your headlights, on as well. Take notes and report back.

There's an unusual aspect of the trailer relay that you should be aware of: There is a small amount of voltage that "bleeds" over from one turn signal output to the other. A volt meter will picks it up and your test light (mine did) might pick it up as well. It's not enough to fire off your car's lights though. What this means is that if you have your test light on the yellow wire, and the turn signal is flashing the green wire, you may see a very dim flash on your test light when it's attached to the yellow light. This is normal.

Digital volt meters are not the best for dealing with flashing circuits. An old fashioned meter with a dial and a needle is better, and a test light is best.

I'm on the case!

OK, I'll split my fee then.:cool:

OK... are we making any progress yet?:confused: The whole diagnosis part should only take about ten minutes or so.