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Discussion Starter · #1 ·
Someone recently tried to steal my 2015 CBR300RA by shorting the wires going to the ignition together. There are heavy gauge red and black wires and a thinner orange wire. All three were tied together when I found it. Check out the pics.

How I found it:


Where the wires go:


First of all, is it even possible to hot-wire these bikes by just shorting a couple wires together?

I repaired the wires and checked the fuses and battery (12.7V). All looks good, but the bike won't start. Nothing turns on when I switch the key to "On".

Does anyone have any idea what may have happened? Is there a fuse for ignition I haven't found yet? Something else that may have fried? I assume twisting the red to black damaged something.

Anyone have a wiring diagram?

Thanks, and I apologize for all the questions :)
Dan
 

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... I repaired the wires and checked the fuses and battery (12.7V). All looks good, but the bike won't start. Nothing turns on when I switch the key to "On".

Does anyone have any idea what may have happened? Is there a fuse for ignition I haven't found yet? Something else that may have fried? I assume twisting the red to black damaged something....
Basically, when the thief bypassed the ignition switch by cutting and jumping the black & red wires together, that had the same result as turning the ignition switch to the "on" position. When they turned the engine off using the kill switch on the handle bar, the rest of the electrical system would have still been powered up, as if the key had been left in the "on" position, and as a result would have eventually discharged the battery. So despite that you've repaired the wires going to the ignition switch, I'm pretty sure your battery is now dead. Put the battery on a 2 amp charger and see if it takes a charge. If not, get a new battery.
 

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Discussion Starter · #4 ·
Turns out I missed the main fuse tucked away by the air box- it was blown. Thanks for the replies. It runs now.

I really hope starting the bike isn't as easy as shorting red to pink. Hard to find info on how that circuit works- for good reason I guess.
 

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Discussion Starter · #6 ·
I didn't even know I could lock the steering wheel! Glad you said that.

I would guess you could still start the bike, but you'd need to break the steering lock to go anywhere. Just a guess since hot-wiring bypasses that assembly altogether.
 

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I am not sure about this but I think if the steering is locked the bike can not be started. Was your steering locked?
The handle bar lock is a mechanical system, and is not interconnected to the electrical aspect of the ignition switch.
 

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The handle bar lock is a mechanical system, and is not interconnected to the electrical aspect of the ignition switch.


Sorry, I wasn't clear about what I was writing. You are correct of course.
I was just trying to explain the purpose of the zener diode. The diode prevents hot wiring with out a key and explains the blown fuse. The diode is not
explained clearly on the wiring schematic but would be a simple way to
prevent hot wiring.
 

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So how that diode works on the cbr is the diode puts out exactly 9v in the initial start up , the ECM receives the 9v in a sort of handshake. After the ECM receives the "handshake" the fuel pump will be triggered. After the bike starts the diode will no longer be required, the handshake will be valid for 30 seconds after the bike is still shut off.

When the diode blows in the ignition from hotwiring it is caused by the 12v constant power to the ignition being supplied reverse into the diode when it is meant to supply the 9v conversion to the ecm.

This will also cause the main fuse behind the air filter to blow.

When the diode has failed it can be emulated with a regular 9v battery from the positive (+) battery terminal on the 9v to the orange wire (cbr300) or the pink wire (cbr250) and the negative(-) terminal on the 9v to the negative 12v battery terminal.

This will mimic the diode. Causing the Fuel pump to engage.

Please correct me if I am wrong but my bike was once successfully stolen and never started.

Also you can mimic the diode with the 9v battery and then use a toggle for the two other wires to the ignition. These ignitions are a hassle to replace because of the headless bolts I believe.
 

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So how that diode works on the cbr is the diode puts out exactly 9v in the initial start up , the ECM receives the 9v in a sort of handshake. After the ECM receives the "handshake" the fuel pump will be triggered. After the bike starts the diode will no longer be required, the handshake will be valid for 30 seconds after the bike is still shut off.

When the diode blows in the ignition from hotwiring it is caused by the 12v constant power to the ignition being supplied reverse into the diode when it is meant to supply the 9v conversion to the ecm.

This will also cause the main fuse behind the air filter to blow.

When the diode has failed it can be emulated with a regular 9v battery from the positive (+) battery terminal on the 9v to the orange wire (cbr300) or the pink wire (cbr250) and the negative(-) terminal on the 9v to the negative 12v battery terminal.

This will mimic the diode. Causing the Fuel pump to engage.

Please correct me if I am wrong but my bike was once successfully stolen and never started.

Also you can mimic the diode with the 9v battery and then use a toggle for the two other wires to the ignition. These ignitions are a hassle to replace because of the headless bolts I believe.

Wow, thanks for explaining this. It's a little bit mind blowing though.
When you got your bike had it been hot wired?
 

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I got my bike from a dealership repo , I payed 3200$ for it . Brand new . 200 miles was all. Then it got stolen and was recovered a month later. They were not able to start it and fried everything. So I had to learn everything top to bottom. (;
 

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Wow, thanks for explaining this. It's a little bit mind blowing though.
When you got your bike had it been hot wired?
I see your in phoenix before I moved back to washington I used to take it to the bike show in scottsdale every saturday.
 
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