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Alright, so I’m new to the forum. I have a little side business of working on bikes and 4 wheelers and what not and I’ve ran into an issue with one of my customers bikes. When I picked it up he had tried to wire in a new ignition by cutting the wires and splicing them and he had extra wires it was the wrong switch it was just a mess. So I took it back to my shop to check it out. When I turned the key the bike lit up but no response from the starter button. It doesn’t turn over or anything. So I put it in dealer mode since it was throwing a code. It said c42 which is improper signal to the ecu. Well I got a new switch. The right one, plugs right in, turn the key lights come on but still no response at the start button and it still says c42. It is important to mention that the wires were just twisted together and that it did turn over once for my customer when he connected the brown and orange wire. So my train of thought is somewhere along the line either when he was wiring it or afterwards when the connections were all right next to each other exposed they crossed and it blew the ecu?? I’m at a loss I just need some direction here, thanks in advance for the help.
 

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Welcome.

If the ECM is giving you a fault code it is highly likely that it is fine. Most of the bad ones, don't send any data to cluster so "CHEC" shows in the temperature window.

I think you have two issues. First, when you say you got a "new" switch, do you mean an OEM part or an Ebay crap Chinese switch? There is a resistor built into the OEM switch and the ECM will throw the C42 code if it does not see it. The Ebay switches look and fit like an OEM switch but there have been a number posts where they did not work. You can do some research on how to wire a resistor in but you would save a lot of time by just getting the OEM one.

Second, as I remember, the starter will work even with the C42 code, it just won't start or run. The most common reason for the starter not to work is the clutch safety switch not being released with the lever back. Of course your customer might have "fixed" more things so it might be screwed up also. A wiring diagram is your friend.
 

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Discussion Starter #3
Welcome.

If the ECM is giving you a fault code it is highly likely that it is fine. Most of the bad ones, don't send any data to cluster so "CHEC" shows in the temperature window.

I think you have two issues. First, when you say you got a "new" switch, do you mean an OEM part or an Ebay crap Chinese switch? There is a resistor built into the OEM switch and the ECM will throw the C42 code if it does not see it. The Ebay switches look and fit like an OEM switch but there have been a number posts where they did not work. You can do some research on how to wire a resistor in but you would save a lot of time by just getting the OEM one.

Second, as I remember, the starter will work even with the C42 code, it just won't start or run. The most common reason for the starter not to work is the clutch safety switch not being released with the lever back. Of course your customer might have "fixed" more things so it might be screwed up also. A wiring diagram is your friend.
I got the switch from Motorsport.com it was listed as a switch specifically for this year and model with good reviews. So assuming this switch is okay what else could it be?

I’ll check out the clutch safety switch in the morning when I’m back in my shop.
 

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So assuming this switch is okay what else could it be?
I think you are assuming too much.

@billv didn't you post not too long ago what voltage the wire with the resistor off the ignition switch (orange with yellow stripe) should read when connected to the ECM? Was it about 8 volts?
 

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Discussion Starter #7
I think you are assuming too much.

@billv didn't you post not too long ago what voltage the wire with the resistor off the ignition switch (orange with yellow stripe) should read when connected to the ECM? Was it about 8 volts?
Okay I checked the clutch switch I was just loose or something a little jiggle and the bike turns over now. That being said I pulled the ignition switch apart and checked the board. There is a resistor wired in between the red wire and the orange with yellow stripe as you said.

Where does this leave me? Is there something after the switch and resistor that could be causing the c42?
 

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It's somewhere around 8 volts (or maybe 6). The level is low enough that the the bike won't run at that voltage. You can check it with a needle inserted past the insulation on the ignition switch connector so that it touches the terminal. But the ultimate place to check is at the ECM. There it runs to pin 21 on the black connector. It's the O/Y lead. Things must be connected. You could also disconnect the ignition switch and measure the resistance between the connector terminals for the R or O leads and the O/Y lead. It should be 100 ohms. However the voltage measurement is more definitive.

Motorsport.com is a site that follows F1 racing.
 

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Discussion Starter #9
It's somewhere around 8 volts (or maybe 6). The level is low enough that the the bike won't run at that voltage. You can check it with a needle inserted past the insulation on the ignition switch connector so that it touches the terminal. But the ultimate place to check is at the ECM. There it runs to pin 21 on the black connector. It's the O/Y lead. Things must be connected. You could also disconnect the ignition switch and measure the resistance between the connector terminals for the R or O leads and the O/Y lead. It should be 100 ohms. However the voltage measurement is more definitive.

Motorsport.com is a site that follows F1 racing.
Sorry I meant motosport.com

I see what you’re saying. I’ll grab my meter in the am and check it. Now unfortunately I don’t get service at my shop atm so in case it all checks out fine would that mean the ecu has a problem?
 

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Discussion Starter #10
Okay the resistor is in the ignition switch, everything looks like it’s working right except the c42 code won’t go away. Is the ecm all that’s left?
 
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