mystery connection next to fuel sender connection

[spoonyluv]

Hey guys. I'm currently working on a 2002 Katana 600 that was brought in for no spark. Everything checks out and we've replaced all the component (igniter is from ebay, but the chances of two bad igniters is pretty low). The source voltage for the ignition comes on a O/Y wire. There is a two pin connector next to the fuel sender connection with an O/Y and B/W. I can't find it anywhere in the wiring diagram. Does anyone have any idea what the plug is and whether is can be my problem?

[92xjunker]

Not all connections are used. Did you test the pulse generator?

[spoonyluv]

I did. 165 ohms and it's showing over 1 VAC signal. We replaced it anyway because the ignition mate was only showing .5 VAC.

[Kreylyn]

Is this a stock bike? Any modifications on it?

Krey

[spoonyluv]

Yeah, stock bike. Does anyone have a Katana in there garage they can take a look at for me real quick. It's a black, rectangular, two pin connector coming out of the harness where the fuel sender does. Orange w/yellow tracer and Black/white.

[92xjunker]

If it doesn't show in the wiring diagram, it isn't used. just checked the diagram. It appears to be for the UK carb heater circuit. The North American bikes use no such connection.

[spoonyluv]

Damn, back to the drawing board! This one's stumping me, which means it's probably something stupid simple. I've got battery voltage at the ignitor, battery voltage at the coils, new coils, new plugs, good pulse voltage from the new pulse generator and good connections throughout. It's got a chinese ignition switch, but all the right wires have continuity in the ON position. Thanks for checking on that anyway.

[92xjunker]

The side stand switch and relay can be the issue.

[Kreylyn]

...... It's got a chinese ignition switch, but all the right wires have continuity in the ON position. Thanks for checking on that anyway.

Now, that's not OEM... The reason I asked if there were any modifications. Lol.

So... the question is does that ignition switch include the correct resistor the OEM switch has. This is needed because the ICM won't fire the bike if it detects the wrong output from the switch to the ICM. It's a security feature to help prevent people from hot wiring the bikes for theft.

Krey

[spoonyluv]

I think you may be on to something there. Do you know if there is any info about the resistor in the manual? All I've found so far is the switch connection chart.

I seem to remember something from MMI about a resistor on the gray wire.

Orange/Red is the only wire I see that has a direct connection to the ICM.

[Kreylyn]

I think you may be on to something there. Do you know if there is any info about the resistor in the manual? All I've found so far is the switch connection chart.

I seem to remember something from MMI about a resistor on the gray wire.

Orange/Red is the only wire I see that has a direct connection to the ICM.

There may be some info in the factory service manual. I've not seen anything in the aftermarket manuals like haynes. I don't even have the specs on that resistor. I remember it being discussed in chat with a mechanic who did know, and had explained the whole thing, but he didn't want the info to just be spread around. He felt that would defeat the purpose of it being there if it was easily found on the web.

A google search pulled up a few other bikes that also have a resistor security setup, and lots of discussion on it. So... that may be a source to look at.

Krey

[spoonyluv]

Thank you

Thanks to everyone who helped out on this one. An 02' Katana 600 does require a 100 ohm resistor in between the orange/red and black wire at the ignition in order for the ICM to spark. That was a tricky one since there is absolutely no mention of it in the factory service manual. You just have to know.

[GaryS-NJ]

Functionally, which wire is the orange/red? And can I assume the black wire is ground? So you grounded the orange/red wire through a 100 ohm resistor? Anyone know what year the Kats started using the resistor?? I've got wired my '84 yam venture and replaced switches on my '83 xj550 and I think on my '78 cb750... Chinese switches.. And mechanically, where is the resistor placed?

[robsmith162]

I have the same issue. So you put a 100 Ohm resister across the R/O and B/W and it then got spark?

[92xjunker]

That is a security feature that shouldn't be discussed.