83 GS 750 T Brake light issue

[abkierstein]

Hey guys, my brake light just malfunctioned today. The running lights work on in and the strand in the rear bulb is fine but when I hit either the front or rear brake, the brake light does not come on. Checked the fuses, everything is fine. Got any ideas?

[Steve]

First of all, ...


Now go check your ground connections for the rear light.

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[chef1366]

Did you try another bulb?

[abkierstein]

The connections are good at all points that I can tell right now. As I already stated the bulb is in good conditino and both strands are intact. I want my brake light back.

[groundshock]

Try a different bulb. It might look ok, but still be bad. after that, use a multimeter to check for voltage.

[Steve]

OK, let's back up a bit, here. You say "The connections are good at all points that I can tell right now." How are you checking them? If you are just looking at them, maybe even pulling them apart and pushing them back together, that's not enough. Do you have a test light? A good test light and a digital mulitmeter should be two of your best friends when working on old bikes like ours. You only need the test light for this problem.

I will now elaborate on my previous statement:

... check your ground connections for the rear light.

Use your test light to verify power at both terminals in your brake light. Connect the ground clip of the light to the negative terminal of the battery. Use the point to verify power at both terminals. If you do not have power at both of them, you at least know where to start looking. If you DO have power at both of them, move your ground clip to the positive terminal of the battery and touch the point of the light to the outside of the bulb socket. The light should come on. If it does not, you have a bad ground.

Do your turn signals and horn work? They are powered by the same fuse as the brake light.

Not enough details in the original message about one thing...you said that when you apply either brake, the brake light does not come on. Understood. Question: does the tail light stay on, or does it go off? If it goes off, it's guaranteed that it's a ground problem.

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