turn signal problem

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onefast1

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Turn signal problem on a 72 Demon: I have power to flasher but when I put the signal on it loses power to flasher. Thanks in advance.
 
This might indicate a bad fuse or poor connection at the fuse clips, or even, a bad flasher or socket.

Just check with your meter, see if you have power at the flasher connector, and if not, go right to the fuse panel.

Even a test lamp is probably good enough in this case
 
I do have power at flasher until I turn signal on then no power at flasher. I have tried a new signal switch also and get the same result.
 
I do have power at flasher until I turn signal on then no power at flasher. I have tried a new signal switch also and get the same result.

Do all of the tail, grill and marker lights work?

It could be going to ground, I would check all of the sockets, and all of the grounds.
 
As mentioned above; sockets, grounds, and the possibility of a bulb with a crossed filament. I've seen this a few times when a filament breaks and lays across the other one.
 
Still having problems, if brake lights are on and you turn either signal on the brake light goes out. left and right both do it. Ran power to each light front and back at switch connector and each light worked fine all 4 corners.
 
Having chased down all of this stuff myself, I was amazed at how many connections (positive, negative), relay internals, bulb sockets, body grounds were corroded. Literally took me months to go through all the circuits that were not functioning properly.

On the turn signals after fixing connectors, bulb sockets, bulbs and replacing the relay that was internally corroded - I had the wrong type of turn signal relay.

Did I say months? As I posted elsewhere, I got in the habit now of putting electrical grease on and around all connections to try to keep future corrosion away.

I heeded the advice here and the only real way to do this is to connect everything up the way it is supposed to be and test every single connection, positive and negative. i.e. You should be able to power the positive side of the relay and have blinkers. As well, I added more ground connections where I thought the factory connections were weakest.
 
Still having problems, if brake lights are on and you turn either signal on the brake light goes out. left and right both do it. Ran power to each light front and back at switch connector and each light worked fine all 4 corners.

Um? This may be normal

With TS switch centered both brake lights work

With TS switch on L turn the L brake light SHOULD go out (and left turn should flash)

With TS switch on R turn the opposite

TS flash power comes through key to fuse "switched buss" -----through fuse supplying flasher ----- through flasher -------INTO TS switch

You MUST check for flasher power with key on and with TS switch in a "turn" postion to put a load on that circuit. Check for power at flasher and at fuse panel.

Do you have a FACTORY manual? If not download one here

http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617

or more here

http://www.mymopar.com/index.php?pid=31
 
OK if I run power to hot side of flasher they do work! the thing I can't understand is why it has power to flasher until you turn signal on then nothing! Would it be ok to just run a new wire from fuse block to flasher so it is hot when the key is on?
 
OK if I run power to hot side of flasher they do work! the thing I can't understand is why it has power to flasher until you turn signal on then nothing! Would it be ok to just run a new wire from fuse block to flasher so it is hot when the key is on?

You are NOT LISTENING here

HAVE YOU checked power at both sides of the FUSE HOLDER?
 
OK checked every fuse in the holder and had signal on and had power on both sides of fuse, was only checking stop and taillight fuses from the beginning then when I got to the radio fuse checked one side then checked other side when I touched it with the meter it started flashing, cleaned up connections and all is GOOD! My bad just never thought to check the radio fuse! I really appreciate all the help guys a Really big THANK YOU to all the guys that posted on here.
 
OK checked..............., was only checking stop and taillight fuses from the beginning then when I...................

Great!! but this is exactly why you need a service manual. Section 8, electrical, near the start of the wiring diagrams, has charts showing which fuse supplies which loads.
 
OK checked every fuse in the holder and had signal on and had power on both sides of fuse, was only checking stop and taillight fuses from the beginning then when I got to the radio fuse checked one side then checked other side when I touched it with the meter it started flashing, cleaned up connections and all is GOOD! My bad just never thought to check the radio fuse! I really appreciate all the help guys a Really big THANK YOU to all the guys that posted on here.
Getting it repaired is not the end. The end is when you understand why it did not work. Then you will recognize a similar problem in the future. You had a poor connection. The connection would not carry the load of the turn signals front and rear as well as the brake light. The resistance at the poor connection goes up as the load increases, resulting in more voltage lost and less voltage downstream in the circuit.

The voltage available at the lights should be essentially full system voltage and full voltage drop should be measured across the light, meaning from the positive to the negative on the bulb socket. If there is a bad connection anywhere in the circuit, that will cause a voltage drop. Any of those unwanted voltage drops are a loss of voltage available at the bulb. If the system is at 14 volts and you have a poor connection that causes a 6 volt drop in the circuit, then your bulb is only going to get 8 volts. It does not matter whether the poor connection is on the positive side or negative side of the circuit. Any voltage lost in the circuit is voltage not available at the bulb. This applies to any load, not just bulbs.

Now get a wiring diagram, learn to read it and you are all set. Thanks for posting the fix.
 
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