Request help with rear light wiring

[SteveM]

I am lost with 12volt wiring. I have an '84 massey compact with headlights, and two rear lights- a blinker and spotlight. The spotlight did not work upon purchase. Here are the facts, I would really appreciate some help:

1) The wire to the spotlight was in terrible shape, so I pulled it all out. Coming out of the light is one red and one black wire. I hooked it to my battery charger and the light works.
2) under the seat is the junction of wires: there are four female connectors. Two in the middle are joined by plastic, the two outside are free hanging. Currently the (working) orange light requires its red wire plugged into either of the middle connectors. The black wire was connected to the outer female, but I have noticed the light works with out the outer connection (?)
3) I strung new wires from the junction to the nonworking spot light. No luck. I noticed that the working blinker seems to have an extra female connector unused (for adding lights?)

Help! What to do next! /forums/images/graemlins/confused.gif

 

[19th_VA]

Check the grounds carefully.

 

[Anonymous Poster]

Can you provide some more information?

Is the light original equipment, or was it an add on?

Did it ever work (aside from your testing with the battery charger)?

Does it have a built in switch, or does it use a dash board switch? Does such a switch exist?

Is it fused, or does it get its power from a fused source? It should.

Should it be operable only when the main switch is on, or at any time (at the risk of flattening the battery in the latter case)? Which would you prefer?

When dealing with a prior owner's electrical "improvements," it often pays dividends to assume it was done wrong, and to pretty much start over. And this doesn't just apply to tractors.

I'd say you may be at the point where you call a knowledgeable buddy over. Electrical problems can be difficult to track down "long distance." Watching and asking questions can be a great way to learn.

SnowRidge

 

[BB_TX]

Without a schematic/wiring diagram, electrical problems are a real shot in the dark. They can be difficult even with a diagram.
Don't know anything about your Massey. My JD has a multi position light switch that is wired to be on only when the key switch is on. It has positions for flasher only, headlights only, headlights and flasher, and headlights and rear work light. With no diagram, I could eventually find my way thru that mess and find a problem, but it would take a while. If yours is anything similar, the problem could be anywhere from the switch thru the wiring and/or a ground problem. I would try to get a manual with a schematic for this problem and future problems. They cost a few dollars but are worth it.

 

[normde2001]

All you need to do is find a source of 12 volts and run the red wire to it, making sure the light is grounded to the frame. (That's why the other light works without the black wire, ground, hooked up). You can find the +12v. with a volt meter or just hook a wire to the red wire, with light grounded and turned on and probe the connectors with it. When you hit 12v it will light. You can't hurt anything, there is only 12v and ground.

 

[Mark_in_NH]

I would go to your auto parts supply store or even Walmart, Get yourself a Good 12 volt test light. There not expensive.
Test the wires and connectors that you speak of. See what wires / plugs become hot / live when when you turn on the key or when you turn on what switches you have.
Once you now what wires and switches are doing what, you can decide on where to connect your light

 

[SteveM]

We are getting somewhere - I am learning (I can tell from the smoke in my ears)

1) It is a factory light, there is a two way dash switch, verified that the switch, wiring are fine by plugging the working orange light into all connections.
2) I bought a 12v tester. Whoppee here we go. How do I properly ground the one wire?
3) Do I assume that I ground the black wire coming out of the light, red one to 12v?


Thanks guys - I hate to trailer a 3,000 lb tractor to the dealer to fix a light /forums/images/graemlins/smile.gif

 

[RonOKC357]

Electrical 101
Your basic circuit is as simple as your battery and your test light.The (neg) (-) (ground) (black) side of the battery and the (pos) (+) (hot) (red) side of the battery. Your test light has a clip on one end and a point on the other with a bulb in the middle. When you connect the clip (neg) (-) (ground) (black) and touch the point to (pos) (+) (hot) (red) {acting as a switch}, if the battery and bulb are good then the test light will light. This makes a complete circuit or (path). Remember, the confusing thing about the "Ground" side of the circuit is that it is not always a wire, but it will always be some form of a conductor (frame) (bolts) (light fixture case). When checking "grounds" look for the (path) from the component using the electrical power to the (neg) (-) (ground) (black) side of the battery. Loose bolts and rusty surfaces can cause a "no connection". [ By the way] To test this path, put the clip of the test light on the (+) side of the battery and touch the point of the test light , starting at the (-) side of the battery and (probe) the circuit all the way to the component. If the test light comes on the circuit is good, if not, check for loose, or dirty, conditions. Having tested the (ground) side, and proved it to be "good", place the test clip to any "ground" and start at the battery (+) and (probe) along the (+) wire going to the component. Before and after any potential "break" in the circuit, (Fuse blocks, fuse links, switches, push together connectors), if the light comes on the "circuit is good", of not, check that component for (loose wire, blown fuse, switch off, switch bad, connector dirty, connector loose, or possible wires broken inside the plastic covering)((Note: when you test a wire and the test light comes on at one end and not the other then there is some kind of break between those two points)). I know this is a bit long winded, but maybe it will help you and or others.
Ron

 

[Phred]

Steve,

Good advice from the other guys.
That test light is the ticket. Use it to probe all the connections until you understand what gets hot (12V) when the switches are on and off.
But take care that a fuse does exist between the lights and the battery. If something shorts out the battery directly even 12V could be exciting. If you let the majic smoke out you will need to replace more parts to get it up and running.

Fred

 

[Anonymous Poster]

</font><font color="blue" class="small">( If you let the majic smoke out you will need to replace more parts to get it up and running.)</font>

Hooray! Someone else who understands how electricity really works! Just last night, I was explaining to my wife and daughter how smoke is the carrier for electricity inside the wires. They didn't understand, or didn't believe me, or something. I explained that smoke has to be the carrier, because every time you see it leak out, that appliance or tool doesn't work anymore.

For those who are not familiar with that scientific principle, it was first discovered by owners of British cars with Lucas electrical systems.