Electrical Backfeed

[go300mph]

OK you all are very helpful and I truely appreciate it. As soon as a question comes along that I can answer I promise to help but my area of expertise is fabrication. Not internal combustion engines or electrical.

I have a one wire one bulb tail light set up it acts as both the stop lamp and the turn signal, I have two wires feeding power to it, when I hit the brakes the stop lamp powers and backfeeds the front indicator lights as well can I add a diode to the line or any ideas.

I checked archives but no luck
Mick

[trularin]

The back lights are generally a four wire setup.

If you use trailer colors, you can find the code on the internet many times over.

What ever color ground you have, make sure it is tied to ground at more than one or two places. There will be a single wire that is used for running lights and allows the lamps to be in a less than bright state. the other two are for each side, one for right turn and one for left turn.

If you are trying to trick through the electrical with less than the four, you might have a number of problems that will come up. Back feed is one, others may include excessive current draw and light failures.

May I suggest you wire the rear of the car with the four wire system. If you feel inclined to use a diode, it had better be a good size one. the 1157 bulb can draw a few amps when fully lit and it is hot.

The running lights are common to the front and rear and, without the proper power management, will feed the fronts as the rear is activated.

Hope this helps.

[jarendall]

you do have a wiring problem, if properly grounded, the front and rear lights should not cross feed, you are cross feeding through your bulb elements, make sure all bulb housings have a ground wire connected to them, if this is not the problem, then the turn signal wiring is shorted some where, or not properly routed, check your wiring diagram for the turn signals

[strictlypersonl]

You need a brake/signal light relay as used to convert a three-wire car to a two wire trailor.

[go300mph]

I need a tail light that is on when headlights are on and a turn signal that flashes when signal input is there, and stop lamp when brake pedal switch sends signal , I have two wires and one dual filament bulb? I have turn signals and stop lamps together in same circuit via common bulb. If I pull the bulb out there is no back feed. Do I go to a two bulb fixture?

[go300mph]

Then Again had I just read all of your great input I would have learned this, soory for the above post I did not read your replys until after sending , unnecessary message.