Fuse "4" in keeps on blowing


ch33zecake

New Member
So today while I was riding to work, I realized that my blinkers stopped working. Once I arrived at work I went to see if my break lights worked and saw they went out too. The first thing that came to mind was that the 15 amp fuse went bad. I checked that and sure thing it was blown. I replaced the 15 amp fuse with another one and right away it blew as soon as I turned the key.

I have the Motodynamic LED turn signals and LED integrated tail lights. I installed these 4 months ago and never had any problems until just now.

The first thing I did was check all the wiring to see if there was anything loose. I found nothing to be loose or exposed. Then I disconnected my tail light and rear turn signal wires and left on my front turn signals on. I turned the key and the fuse didn't blow. My front turn signals worked perfectly.

The next thing I did was do the same to the tail light and rear turn signals. I disconnected the wiring for the front turn signals while the tail light and rear signals were connected. I turned the key and the fuse blew.

I cut the heat shield on the resistors for the rear turn signals and visually saw nothing abnormal. I'm not savvy with multimeters so I asked my buddy to test the resistors. I'm not sure exactly what he tested, but he said they read the same for each of the two wires (blue and yellow). He's an electronics technician in the Navy so I took his word for it.

I put the heat shield back onto the resistors and taped everything back together with electrical tape. I decided to take the connector for the tail light itself (no front/rear turn signals and any resistors connected) and connect it. I turned the key and the fuse blew.

Now I'm beginning to wonder if something shorted inside the actual LED tail light. I don't have my stock one anymore because I was stupid to let someone have it. Otherwise I would've tested to see if my stock tail light worked. What do you guys think?
 

buzzbomb

Senior Member
Elite Member

ch33zecake

New Member
I've no experience with aftermarket lights, so my advice is sketchy at best.

If the fuse blows when only the rear lights are active, then it seems there's got to be a short in that circuit.

Are you able to connect the rear lights to the front light harness (with the front lights disconnected)? Whether the fuse blows or not might help track the fault.
I don't have much experience with aftermarket lights either. This is my first time I've ever had problems with LED lights in general.

I don't fully understand your question though. Do you mean connect my rear turn signal wire assembly and try to hook it up to the front turn signals? I'm not sure if I'm able to do that because the front and rear turn signal wires have different ends for one side.

So I've tested the front turn signals with everything else disconnected and they tested good. I've tested rear turn signals with everything else disconnected and tested bad. I've tested the rear tail light with everything else disconnected and tested bad.

My buddy tested the resistors on the rear turn signals and measured both 7.5 ohms on the multimeter. Since the rear turn signals are integrated into the tail light, maybe that's the reason why the rear turn signals also cause the fuse to pop? I'm guessing it's a short somewhere on that circuit board within the tail light housing?? I'm getting a replacement so I'll find out here real soon.
 

buzzbomb

Senior Member
Elite Member

ch33zecake

New Member
Ok so I figured out the problem. It wasn't the tail light. It was the two connectors for where the old turn signals used to connect to. The ends on those connectors are both bare metal, and they were touching each other. I don't know how they didn't touch each other 4 months after installing until just now.

IMG_1382.jpg

I taped both those ends with electrical tape. Problem solved. Now who wants an extra brand new Motodynamic Sequential LED Smoked Tail Light? PM me if interested...
 

ch33zecake

New Member
Did Motodynamic send you a replacement for free or did they have you pay for the new one?
Sorry for the late reply, but I didn't even bother to ask if they could send in a free replacement. Yes I should have worked with them more to figure out what exactly the problem was so that they would have a reason to send me one. I just couldn't wait though. My bike is my commuter right now, and my car is having some problems lately. I just bit the bullet and hoped for the best.

I'm glad the problem was something really simple and didn't require a replacement. I've already returned the one I bought from them, and hopefully will receive a full refund.
 

WaistDownSquid

New Member
Ch33zecake, were there ever any more issues with this fuse popping after these posts? I'm going through almost the same exact troubles and want to be sure before putting the bike back together.
 



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