The two wire ends have regular spade terminals which you plug into the panel in place of the fuse. The light is just a regular 12 volt pilot light. The square black thing is just an inline ATO fuse (this fuse is not really necessary). When you plug this in the panel where a fuse constantly blows the pilot light will illuminate (the short becomes the ground for the pilot light). Once you locate and eliminate the short the light will go out. It saves a making a pile of blown fuses while trying to locate the short.
Guess I don't know what the acronym stands for, just know them as ATO fuses. http://en.wikipedia.org/wiki/Fuse_(automotive)
^^^^^^^^^^This is why I'll never understand electricy, way too many terms, and things to measure, and some guys wonder why I worry about electrical fires. Bob
OK... more info. If my problems are self inflected its in a good cause. All rear lights are mounted in the rear bumper. The rear bumper is removable. There are two 4-pin trailer wire connectors back there. One is for ground side only, with a ground wire to each light base. The ground harness is isolated completely from the power side harness, and is routed directly to battery ground. The only addition to that harness is a ground wire to the fuel sender base (mount screw). On the power side there IS a simple splice off to a barrel style (4 pin) trailer light connector. When a test light is used at the pins all circuits check good at both power side to bumper, and at the trailer socket, using the ground side pins. Now... to the bumper. With the bulbs in place I get no more than 0.5 Om through any circuit. When a small battery is used between bumper harness ground and bumper harness power harness (they are isolated from each other) all lights are working. Pin assignments have been checked and rechecked. When I plug the bumper into the main harnesses (power and ground) all hell breaks loose and fuses blow with a loud snap. And yeah... I can't recall ever owining a car that didn't have brake lights with the key off. Todays Pix are attached. Comments are welcome.
I see you are using the odd pin of the round trailer plug as a power wire. I have seen some of the round trailer connecter where the screw that holds the plastic insert into the metal case actually contacts the socket that was intended to be the ground socket. Maybe remove the retainer screws and see if that is your short to ground.
Currently the barrel connector pins are pushed through the housing. The steel pin in the connector is ground through the ground harness. The other 3 (brass) pins are tail lights. Rt and L brake/turn. I have power to all those pins at the right time using the steel pin as ground. Sorry my notes page didn't translate well through the scanner... it shows the pin assignments.
A guy dropped off a 55 chevy sedan delivery for me to finish up some wiring and other stuff. It's an aftermarket harness kit and I noticed that the T/S work without the key on and the brake lights only work with the key on. ARRRGH! sounds like a Rebel set up.
Have you guys called bob at rebel yet? I'm sure depending on what kit you have you could swap out the keyed power for the tails to constant, but it probaly is a safety thing,as if your brak light switch sticks it will kill your battery.
European cars provide power to the brake lights only with the key on. Every American car I've seen does not. I tend to wire my cars so brake lights only work with the key on because people have a habit of resting their foot on the brake pedal whenever they're in the driver's seat, whether they need to or not. I've changed a lot of brake light bulbs and melted taillight housings in my career, probably for that reason.
not really concerned with the brake light/key position right now... just truing to figure out if there is any other logical test I can use to ID this problem. If there is not enough resistance in the circuit maybe? i'm missing something and don't know what it is
I still suspect the round trailer connector. I have seen too many that have cross connections from a variety of things. Sometimes it will be a wild conductor hanging out to the side or touching one of the other terminals, sometimes the conductor is bigger than what the manufacturer intended and then the screws stick out too far and touch the housing. Sometimes the inner plug tilts when installed into the metal housing and the terminals or screws touch the housing. Try hooking the wires up one at a time to it's mate,(eliminating the trailer connector)and see what happens. at least that way if it isn't the plug you'll know which wire is the culprit. If the problem isn't the plug, check the lamp bases for a cross connection to ground. Look at the lamp bases themselves for defects, such as a glob of solder making an unwanted connection. Good Luck ~Alden
Gentlemen... I owe everyone here an apology. I have found the source of my problem and it has nothing what-so-ever to do with the harness or its manufacture. The truth is that this is a World Class Blue Ribbon Award Winning Bone Head Move on my part. There is simply no other way to put it... I screwed up. I now have everything (except E-flashers) working in the lighting system. The real drag is after correcting MY mistake there was no joy in it. I'm sittin' here thinkin' "What a freekin' dunderhead". I can only say in my own defense that I was so twisted up-side-down that I couldn't see the forest for the trees, and that is why I made the original request for another set of eyes on the problem. I'd like to thank everyone who responded to this thread.
C'mon. What was it? We've all been there, and our Buddy happened along to see what we did wrong, before we could hide it...and told everyfreakinbody. Made your face turn red and all. Hey, that's life, huh Unk? So- spill it.
You have to tell us so we can use that as the next answer for 'why does my tire keep going flat ?" question
It was all in the pin connectors to the removable rear bumper. Every check told me that I had complete circuits out of the harness, and complete circuits in the bumper/light harness. What I didn't see... to my everlasting shame... was that the two pin connectors were reversed. I was plugging the power side harness directly to ground. I switched the pig tails on the bumper harnesses (power~ground) and every thing woke up except the E-flashers. It was right in front of me and I didn't see it.
Success teaches us nothing. Wiring is hard to pick up if you've never done it before. I tag EVERYTHING and always try to have the schematic for the car on hand. A test light is a must, a break-out box (with fuses) is a good idea so you don't fry something. Even something simple with a fuse holder inline works. Kudos to you for hanging in and getting it done. I think many have learned something from your trials. Bob
You are BY FAR not the first one to do this, and I am sure you are not the last. Even with all the colors and marks I managed to do the same thing when installing a 6 pin connector on the body. Luckily I caught it as soon as I plugged the connector together. Probably one of the reasons folks charge so much to do it. One small oversight costs a lot of time troubleshooting.
Has anyone thought of a Stupid Simple lighting design? Head, Tail, turn signals, Brake and a rear plate light, have I missed something? How many wires would there be and what gizmos have to be in the setup?
Ha Ha, you knuckle head, I told you it was with the rear lights and told you earlier that you had a power wire grounded somewhere. To bad I couldn't put the two together to figure it out. All this stuff just makes us smarter until we forget it, then we have to struggle all over again. Once I chased a short in my brake lights, I replaced the switch, took all the wires apart at the rear, tail lights off and on. Finally found it shorting out against the transmission case between switch and fuse box, it's all a pain in the ass.
yep.... 'm a blue ribbon ignoramus. I did add red tape (incorrectly) to ID what I thought was the right pair of connectors, and even reversed the pin direction so they could only be plugged in one way. On the bench everything worked... on the truck everything worked. Just another add to a long list of stupid stuff I'v done in this lifetime.
Hey, Mort; Don't feel bad. I work w/mass transit buses, & you wouldn't believe the screw-ups in wiring. From the factories, & some of the techs' "fixing" or 'troubleshooting". Stuff gets put in cross-ways; idiot proof plugs aren't; wires get vibration rub-throughs & short out to ground; "tech" use those G.D. test-light-needle-probes -- which create a *perfect* hole in the wire insulation for corrosion to start & eat up the copper wiring; corroded ground connections; mis-matched color-coded wires in the harnesses, not to mention wire colors which differ from the schematics; the factories use wire that is almost-but not quite-large enough dia, & then to top it off, they run the harnesses short in length, but at least pull them tight enough that you could damn-near strum them like a guitar, which makes repair at the terminal ends a real joy..., although they do put in "blank" extra wires in the harness; & the list goes on. . I've gotten to the point of literally making drawings of both ends of the multi-point terminal, labeling it as to which end of the term I'm looking at, & also writing in the color(s) of each wire to each pin #. & then compare it to the schematics, & maybe another bus of the same series. (Who know who did what to it when). Can get real interesting... . You literally have to forget about time, or you *will* screw it up, causing yourself more grief, if not smoked parts, too. Which adds to the frustration. You did well, & learned how to chase the gremlin. Thanks for posting, esp what you found the original problem to be. A lot of folks have to much pride to admit they *could* have screwed up, but a real man/hotrodder will say " Opps, " & admit it, (no shame in admitting a screwup - the fix can get interesting) for either humor or a learning experience - or both. . Marcus...
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