Brake light/turn signal gremlin

[smurfy71]

82 Seca 400

So I thought the bike was all ready for a safety check so I can get it on the road, but........

I found today that when the brake light is on, the turn signals stop flashing. WTF? I have checked all the wiring, looks good and they flash when the brake light isn't on. Happens with both front and rear brakes, and both l/r, f/r signals.

Could this be a relay? A ground?

 

[16VGTIDave]

Sounds to me to be a bad ground.

 

[smurfy71]

That was my initial thought, but since the signals work as they should until the brake light comes on I want sure. Grounds all look ok, I'll work on it some more.

 

[Slojza]

Also check the battery and charging would be my advice. Takes 2 minutes with multimeter. Then you can look for a bad ground as Dave said.

 

[smurfy71]

Battery is brand new and kept on a tender.

 

[kshansen]

That was my initial thought, but since the signals work as they should until the brake light comes on I want sure. Grounds all look ok, I'll work on it some more.

As a test hook wire to (-) terminal of battery and run it direct to the various lights grounds to eliminate a ground problem. A bad ground may look good but may be bad somewhere you are not seeing. Ground may be good enough to work one light but when more are added to system it can cause all kinds of weird things to happen as theelectricity tyrs to find it's way home to the battery!

 

[Slojza]

Battery is brand new and kept on a tender.

But have you tested the voltage? And if it is getting about 14,5 V when the bike is running? My bike was doing only something like 13,5 V and after few minutes riding my flashers didn´t flash when the front light was on.

 

[smurfy71]

Is there a how too thread for this? I have a multimeter, but no idea how to use it.

 

[Slojza]

I haven´t seen a thread for testing battery/charging but it is very simple. Also you can find it in a manual.

Just set your multimeter to V(Volts), 20V range will be enough unless it is set automaticaly. Then just connect red lead to red(+) and black to black(-) to ground it. The battery should read about 12V or a bit more when the bike is off, if not, charge the battery and see if the voltage gets higher and if it stays on that for, let´s say, a day. If not, then you need a new battery. Without it, the charging won´t work well.

Then do the same while the bike is running. According to manual, if you rev the bike to 2500 rpm it should read 14,5V (+-0,3). If not, look for threads about charging here in the forum, there are many.

 

[smurfy71]

I haven´t seen a thread for testing battery/charging but it is very simple. Also you can find it in a manual.

Just set your multimeter to V(Volts), 20V range will be enough unless it is set automaticaly. Then just connect red lead to red(+) and black to black(-) to ground it. The battery should read about 12V or a bit more when the bike is off, if not, charge the battery and see if the voltage gets higher and if it stays on that for, let´s say, a day. If not, then you need a new battery. Without it, the charging won´t work well.

Then do the same while the bike is running. According to manual, if you rev the bike to 2500 rpm it should read 14,5V (+-0,3). If not, look for threads about charging here in the forum, there are many.

Ok, thanks. I will give it a go.

 

[smurfy71]

Ok so it seems there is an issue with charging. 12.5 volts when off, down to 11.6 when running and stays there. Reving the engine just gives it .1 or .2 more.

 

[Slojza]

Now it is time to look to the manual and play with multimeter some more and find where exactly is the problem. Good luck

 

[smurfy71]

I did a little. The three white wires from the stator are showing 1.2 ohms each, although the manual says this should be higher, but they are all the same.
The field coil is not registering anything.

 

[smurfy71]

So reading the manual and based on numbers above, I'm guessing I need to replace the field coil. Problem is, my service manual doesn't tell me how or even where it is located. Is this part of the stator?

 

[smurfy71]

So today I got around to having a closer look at this. I removed the field coil and found this. My manual doesn't show a breakdown of the coil, but this doesn't look right to me, I think there should be a second point on this?

 

[smurfy71]

So that turned out to be my problem. The field coil was missing a brush. Picked one up at a local shop and presto charging system is again working. And the signal keeps flashing when I pull the brake now.

 

[Slojza]

Great you solved it

 

[smurfy71]

Thanks for your help.