Signal/Brake converter help

R

RuralTowner

Member
I'm thoroughly stumped...

I've tried 2 different tail light converters...a CURT and a HOPKINS. As the rest of the vehicle wiring is in place I only have to finalize the wiring on the arse-end...but I've run into a wall.

I'm doing testing in the back of the vehicle with a healthy battery nearby and grounded with a trio of 12ga leads with alligator clips. The first negative (battery to vehicle) is latched onto a solid ground on vehicle. Another negative lead (starts at battery) is set to the GROUND on the converter which frees up using of the HOT lead to test connections. As the vehicle has an open top I'm using a work light in the dark to see so I can be inside and look outside to see the lights light up the wall behind the vehicle.

For some unknown reason the CURT (the 2nd one after the 1st somehow died) will now only operate the running tail lights now. Can't get any current through BRAKE side or signals. So I got a new HOPKINS today and hooked it in.
Grounded? CHECK
Brake lead lights up lights? CHECK
Briefly test signal leads w/o relay? CHECK---Both will light individually.

HOWEVER when I put the signal relay between the HOT and either LEFT or RIGHT lead going into the converter...no clicky clicky from the relay or lights lighting up. But if I connect the relay to the tail light lead...it works. The signals will still light up if fed direct power.

I'm using a relay that actually has guts (clear casing so you can see the capacitor and armature move when its working). Can hear//see it work when hooked up to the tail light lead. But no activity (light or otherwise) when trying to power the signals.
 
Not enough information. Is this for a trailer connect or is it for a separate light assembly? Also, what type vehicle and what voltage does it operate with?
 
"rotorwrench" - I did a "Google" search and I think you're right It's kind of satisfying, the confidence that some people have for this site and it's members. O/T, but still satisfying.
 
I tried to use a trailer converter on the back of a 36 coupe I built a few years ago. ended up more complicated than I thought. The converter was to run a trailer on the system that used the stop lights as the turn signals, and was intended to be powered from a vehicle that has separate orange turn signals (or red, just separate from the brake lights).

I had to wire the car with a full set of lights and hide the rear lights in the trunk. The "trailer" lights were then fitted to the back of the car.

It wasn't worth the trouble.

Anything since then has either been wired with a switch that does all the switching or my own system that used a couple of dpdt relays.

Mart.
 
I have seen some those units that defy normal testing as the module (internally) uses the opposite side brake light filament as a ground.
 
The vehicle was custom built by my dad back in the 60s using a couple 53 Mercurys using only the frame/drivetrain + firewall out of one and the rear end of the other + enough of the frame to permit building a tandem axle setup. The body is designed to resemble a WW2 scout car (currently with fixed louver grille...this will be changed to moveable in the near future). The original 6V generator was changed out to a 12V long ago and so that's the voltage it will be using. As mentioned all the lighting wiring is place but is currently disconnected in the backend until the signal issue is resolved.

All testing is currently being directly at the converter input leads with a 12V battery grounded to the vehicle and to the converter ground lead. Grounds are good since the tail lights work...brake lights work...signals light up when fed direct power but will NOT function when powering through a relay yet the tails will.

The setup is so the vehicle will have functional signal and brake lights on 1 pair of bulbs (1 left 1 right) AND to make it street legal. It will also permit easy hookup for any future trailer made to match. As there is nothing left of the original steering column there is no way to isolate brake from signal without going a complex route of multiple relays. IE a left and right relay and separate brake relay that keeps the signals isolated from one another until the brake is pressed.

I have an identical converter connected to my daily driver...and though it has separate brake//signals to start with, what I'm trying to do is functionally the same. The converter in it works just fine when hooked up the trailer I have for it. Bot this unit and the one that is giving me fits have the ground lead (complete with eyelet) on the input side).

I'm just puzzled why I can't get the signal lights to blink when powering the input leads through it yet I can make the TAIL lights blink.
 
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Could it be the relay I'm using somehow TOO heavy duty? Would think the signals would draw more amperage and thus get the relay to operate. Or being finer filaments to get brighter light draw less while the tails are more robust and so draw more power to allow non-stop use and also provide dimmer light?
 
Rural - what are you wanting to do?

Sorry but it is difficult to follow statements like "For some unknown reason the CURT (the 2nd one after the 1st somehow died) will now only operate the running tail lights now." when we don't know why you bought a CURT in the first place or what a CURT is intended to accomplish.
 
I'll get some pics of while there's still light. One of the half-track scout ones is what its meant to resemble. Will have to forgive the current rims on it though...mags that already had tires mounted that work in the interim so it can move while getting other tires for the rims already had for it.

UPDATE: Powered the tail lights through the relay and as mentioned they will flash. Then when I add either or both of the SIGNAL leads to the power with the tails then they will flash too. When I stop holding the tail light lead to the power...the signal stops blinking also. Now this DOES make me think the relay might be a tad too heavy duty.
 
The old add on signal kits generally had brake light switch input so that the unit would separate the two for turn signals. A person could use a hydraulic or mechanical switch for brake input. I hope you can sort it out. It would be easier if it had two light per side with the bright bulb for brake & turn + dim one for running.

The old lynx scout car wasn't much to look at either.
 
.......

THIS is the converter in question. See image below.

Nothing exists of the original vehicle wiring. No signal kits. It is wired to use a 3-position switch to operate the LEFT//RIGHT turn signal. The LEFT//RIGHT leads from switch are meant to go to their corresponding inputs on the converter. Already have a brake pressure switch in place. It works and the outbound power lead form IT goes into the converter.

ALL NORMAL driving lights work. It HAS headlights...tail lights work TOO (lead connected to converter). I just cant get the **** converter to operate the signal lights. With a signal relay between live power and either LEFT or RIGHT signal wire...it will NOT work. It WILL however light up the signal bulb if powered directly (no flasher relay).

The only lights that will operate with the flasher relay are the tail lights. This was done as a test to try and troubleshoot.

It will not operate LEFT//RIGHT signals even when powered together in ad-hoc "hazard" test. They WILL flash only when joined with the tail lights and will stop flashing when I remove power to the tails.

Photobucket has gone 1990s on me with old fashioned text and hyper link words only when it does finally load. Otherwise I get a "page cannot be found" Will get images up later.

I'd LIKE to try and preserve the military-esque look of the rear w/o adding unnecessary legal lighting if possible. Others have used converters like the one shown below with positive results. The vehicle HAS military blackout lights on the rear but those aren't road legal I'd imagine unless you're in a proper convoy where only a stupid cop would pull you over. With only 1 red tail light and 1 red brake (separate bulbs in 1 light assembly) while the separate small triangular "you are following at the right distance" indicators that are barely visible beyond a few hundred feet.
 

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I have the same converter in the daily driver and trash hauler pickup and they work just fine. Both have separate turn//brake and are wired into the converter no differently than what I'm trying to do here except the one in question goes to lights already on the vehicle instead of to a trailer. In both cases the ground on the outbound side of the converter is either grounded or left hanging...works either way.

Since photobucket on my end is suffering from who knows what...here are direct uploads.
 

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The difference between your daily and trailer and what you are attempting is that there is a set of lights upsteam from your converter on the former; similar to what Mart was referring to in post 4.

Back in the dark ages, we tried several different converters when mounting US truck bodies on the early Asian import trucks; found the converters didn't test "normal", some didn't work as stand alone units, and none of them lasted very long in daily service.

It sounds like you are finding these will not work the way you want; maybe just use some 5 pin relays and be done with it.
 
By upstream...meaning lights up front? The wiring is run...just nothing at the front end of the wires. Might connecting lights up there get it to work? Have been tossing around the idea of disconnecting the little bullet-type blackouts (they are missing the pieces in their windows to reduce the light so they instead put out full light through the lenses) and turn them into signals.

Never dealt with 5-pin relays before so not sure where to begin.
 
By "upstream" I mean your daily has a set of lights, then the converter, then the trailer.

On your scout car you have the converter, then a set of lights; no first set of lights.

If your converter relies on the opposite signal filament as a ground (internal to module) you are lacking the set of lights that would provide those grounds.

Maybe stick a set of dual contact sockets in the black-out lights and use them as the first set of lights and feed your regular lights off the converter.
 
I think I see what you mean now. The reason why the tails would blink is because they are already grounded to the body...and why when I combined the signals with them THEN pulled the tail...they lost their ground. Nothing for the relay to ground to. While directly powering the signal leads also completed the circuit.

The front blackouts only accept single filament bulbs...but as mentioned they lack the extra little block-off cover inside to function as "proper" black-outs but they would work fine as front-end signals. The leads for the dead-end front signal wires share the same section of loom anyhow so I'd only have to swap connections. Will free up both black-out leads for an eventual pair of BO headlights...won't have to piggy-back with the small ones.

Will do the changeover tomorrow and see how it works.
 
OK I give up. I cannot understand what is going on because of the strange language short cut words which have no meaning to me. I'm only an EE but when no one will say what a signal is (I'm also a ham and don't know what frequency the signal is) and converter ... converts what to what? Don't try to explain - I don't need to know. Strangely I do know what upstream means but it's unlikely the same meaning as others use it.
 
Nothing to do with frequency. The converter mentioned is usually used when you have a vehicle with separate brake//turn signal lights and want to connect to a trailer where the brake//signal share the same bulb.

It's about the size of a cigarette pack with 5 wires going in...1 ground...1 for tail lights...1 for left turn...1 for right...and 1 for brakes.

On the other end it only has 4 wires. Ground to help ground the trailer (normal usage) since can't always rely on the trailer to ground on the ball hitch. The other 3 wires are left and right turn...and tail. So when you press on the brake pedal it tells the converter to light up both signal lines without having to run a whole separate set of wires to their own bulbs.

It can also be used to get brake//signal lights to work again on a vehicle that has just the 1 set of bulbs when the original signal harness in the steering column no longer works or is absent (as in my case).

What was happening here is I couldn't get the rear turn signals to light up properly since it seems to require my having intact turn signal lights up front to help complete the circuit.
 
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