CLAYA

Understood, But the ignition circuit is similar, so expect some will have some insight.

Curiously, there was a resistor lying on top of the head, but never installed. Suspect the PO had planned on using it but the switch bypass worked without it.. Till now. The signal generator coil magnet is broken in 3 places. I superglued the magnet back together, and the sig gen pulses look a little better on a scope, but still no square wave output from the ICU. Shouldn't the pulse signal be a sine wave? Or at least 3 of the 4 pulses be an AC sinewave? (100 ohm resistor to ground.) Unlike the Bandit, there is no orange/yellow wire on the ignition switch of my 06 Katana. But there is a orange/yellow on the ICU. If it eventually gets pulled toward ground, I cannot see where that happens. Are you suggesting the ICU ignition input is active low? Does anyone know what voltage should be on the ignition input pin on the ICU?

06 Katana 600F. Same issue, No spark. Have checked the coil inputs, ignition and interlock, pulse generator signals to the ICU. 12.4V at the battery and interlock input. 11.2V at the ignition input. 12.4V at the coils. Pulse generator pulsing. No square wave at the output of the ICU. (I see very noisy short pulses on a o-scope at the ICU output, but not nice square waves like I am expecting) I cannot figure out the neutral switch voltages at the ICU. Can someone help with that? The neutral light is ON, but what voltages should I see at the ICU for the Neutral inputs? The coil input voltage drops to about 10.6V when the starter is spinning, which does not seem right. Does anyone have voltage and signal levels at each ICU Pin? I can only find partial voltages and signals in the service manuals, and online. I think the ICU is bad, but without knowing what the correct voltages, and signals at the ICU I cannot test it. History: Bike has been down a LOT. Previous owner wired in a toggle switch in place of the ignition key-switch, and has been running fine with 12v to the ICU input. But suddenly it has no spark. Is it possible the 12V input to the ICU has blown it out? The kickstand and clutch switches do nothing. The starter spins regardless of the clutch and kickstand position. I see no evidence of switch bypasses.