My Bike Has No Running Brake Lights, What Gives? | GTAMotorcycle.com

My Bike Has No Running Brake Lights, What Gives?

Pegassus

Pegassus

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My Bike Has No Running Brake Lights, What Gives? (Solved!!)

It's not the fuses, I checked them, when I apply the brakes they work but not when the bike is running.... therefore I can get rear-ended at night. What can it be? They were okay earlier today and then nothing this evening. I did change a burnt brake lightbulb but after replacing it they worked, but not after a few hours of riding. My licence plates are in the dark when I ride at night.
 
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Pegassus said:
It's not the fuses, I checked them, when I apply the brakes they work but not when the bike is running.... therefore I can get rear-ended at night. What can it be? They were okay earlier today and then nothing this evening. I did change a burnt brake lightbulb but after replacing it they worked, but not after a few hours of riding. My licence plates are in the dark when I ride at night.
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A start might be, what bike do you own? Do you have the service manual for it? Use a multimeter to check for voltage at the license plate light and work backwards following the service manual. When my license plate light quit working the relay under my seat was almost popped right out of its socket (probably due to my crash). Pushed it back in, tada, license plate works peachy. I believe that same relay controls ALL of the "running" lights on the bike (tail light, the little peanut bulbs in my headlights, etc.).
 
johnscruiser said:
A start might be, what bike do you own? Do you have the service manual for it? Use a multimeter to check for voltage at the license plate light and work backwards following the service manual. When my license plate light quit working the relay under my seat was almost popped right out of its socket (probably due to my crash). Pushed it back in, tada, license plate works peachy. I believe that same relay controls ALL of the "running" lights on the bike (tail light, the little peanut bulbs in my headlights, etc.).
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Hmmm I will try this, maybe I pulled something under my seat? I was trying to accommodate my goggles and gloves inside that little compartment under the seat. I've noticed there's lots of little black boxes with relays in them, will take a look come tomorrow morning, thanks!
 
Pegassus said:
It's not the fuses, I checked them, when I apply the brakes they work but not when the bike is running.... therefore I can get rear-ended at night. What can it be? They were okay earlier today and then nothing this evening. I did change a burnt brake lightbulb but after replacing it they worked, but not after a few hours of riding. My licence plates are in the dark when I ride at night.
Click to expand...

Brake light filament in the bulb is different from the running light filament in the same bulb. Try changing the bulb with another new one. Also check your contacts in the light socket for corrosion.
 
griff2 said:
Brake light filament in the bulb is different from the running light filament in the same bulb. Try changing the bulb with another new one. Also check your contacts in the light socket for corrosion.
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I'm aware that a brake lightbulb has two independent filaments, one works when you apply the brakes and the other one is courtesy light. Both were working until this afternoon, maybe I pulled something loose when I was trying to cram stuff under my seat. There is no corrosion because they were working fine this morning.
 
Pegassus said:
I'm aware that a brake lightbulb has two independent filaments, one works when you apply the brakes and the other one is courtesy light. Both were working until this afternoon, maybe I pulled something loose when I was trying to cram stuff under my seat. There is no corrosion because they were working fine this morning.
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Last week I changed a dual filament turn signal / running light. Running light worked, but not the signal. Reinstalled, and realized the bulb wasn't sitting properly so it wasn't making the needed connections. Could this be it?
 
I had this happen with my ignition switch, essentially I was between off and run and this caused the exact symptom. It was a drz400sm.
 
Pegassus said:
It's not the fuses, I checked them, when I apply the brakes they work but not when the bike is running.... therefore I can get rear-ended at night. What can it be? They were okay earlier today and then nothing this evening. I did change a burnt brake lightbulb but after replacing it they worked, but not after a few hours of riding. My licence plates are in the dark when I ride at night.
Click to expand...

Check the battery voltage with the engine running at, say, 3000RPM.

If your charging system is overcharging you can burn out light bulbs like this. If you're seeing more than ~14.8V I would be looking at a rectifier/regulator assy for your bike.
 
griff2 said:
Brake light filament in the bulb is different from the running light filament in the same bulb. Try changing the bulb with another new one. Also check your contacts in the light socket for corrosion.
Click to expand...

Joe Bass said:
Last week I changed a dual filament turn signal / running light. Running light worked, but not the signal. Reinstalled, and realized the bulb wasn't sitting properly so it wasn't making the needed connections. Could this be it?
Click to expand...

LOL!! Thanks to both of you!! I thought you guys were being silly but I went outside early this moring to my bike and just for sheet & giggles did what you guys told me and BAM! The running brake lights came on!! I took out the brake lightbulbs and reinserted them into the sockets.

I also noticed that you cannot put them on the wrong way even if you wanted to, there's only one way for them to go in. Thanks guys.
 
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Re: My Bike Has No Running Brake Lights, What Gives? (Solved!!)

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