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Do you have the service manual?
  1. Check that the main fuse (30A) is good.
  2. Check that the cables are tight at the battery and at the starter motor.
  3. Check that the battery is charged and good.
  4. Check the starter motor relay.
  5. Check neutral switch is operating.
  6. Continue down the troubleshooting diagram in the attached images.
Organism Font Slope Rectangle Parallel

Font Material property Screenshot Parallel Rectangle

Font Parallel Number Screenshot Document
 

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I'm going to jump in here, not so much because I can help, but because I'm interested in learning more about the VLX's starting circuit, and I'd like this thread in my watch list.

To the OP, I'd suggest spending some time looking at the service manual. In addition to the link that M'OtherOrb provided, one can get the '97 and later manual from this source. It's not the highest rez scan, but some of the information may be different.
Shadow VLX 600 Service Manuals - VT600VLX.com

Thanks to M'OtherOrb for posting this detailed information.

I notice that the troubleshooting diagram for the starter circuit in the '97 and later manual is somewhat different.
Product Rectangle Schematic Font Slope


Do the earlier VLXs not have a neutral indicator light? Can anyone describe what the function is, of the back to back double diode in the ground circuit of the starter relay?
 

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I notice that the troubleshooting diagram for the starter circuit in the '97 and later manual is somewhat different.
View attachment 298253

Do the earlier VLXs not have a neutral indicator light? Can anyone describe what the function is, of the back to back double diode in the ground circuit of the starter relay?
It's been a long time since I've worked on these kinds of circuits in much detail, so I may have this incorrect. What follows is my supposition, even though it's written as fact.

That's probably a bipolar junction transistor (NPN). In this case, it looks like it's being used in "transistor gain" mode to use a relatively small current coming from the ICM to control the much higher current to the starter relay. In one, limited, sense you can, sort-of, think of this as a solid state relay (but it's also not). These were used before integrated circuits became more important in the automotive industry.

This is also an example of why it's incredibly important not to just rip circuits out of an automobile. Removing that seemingly unimportant part very likely can stop the entire circuit from working properly. When we get into transistors and ICs, the system can no longer properly be thought of as simple plumbing with electrons. Back when we had basic magnetos, incandescent bulbs, and straight-forward electro-magnet solenoids for starters, we could cut out whole wiring harnesses, but now, even with a motorcycle as old as a 1997, we're looking at sophisticated electronics that rely on non-intuitive components to operate.
 

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what i cant figure out is why my icm has two wires cominug from every plug
The wiring diagram tells you where each of the wires goes. In the diagram, there's a solid circle when two lines connect, this is showing a junction between two wires, but it's just a schematic. They don't show two lines coming from the ICM because it would be too messy on the diagram. Instead, they show a junction to indicate where the two (or more) lines run. When you look at the ICM part of the wiring diagram and follow those lines, you'll see that there are junctions for (almost?) every line, meaning the ICM connects to multiple components through those wires. I recommend you take the wiring diagram, print it out at high resolution, and highlight each ICM wire according the color codes given in the diagram. Take that out to the bike and trace the diagrams. If you've already stripped/cut up the wiring harness, this is going to be significantly more difficult but not impossible.

The right way to strip down the wiring is to disconnect one component at a time, check the bike for operation of all parts you need/want, and if everything is good, tag that plug for removal. Leave the component disconnected and then go to the next component. Don't remove the wires until you've checked that the bike runs when every component you don't want is simply disconnected. Then run through a second time, splitting the component wires out, clipping them where it make sense, and then testing the bike again. If you have to add back a wire/plug/component, you know exactly which one it is and can do so with just that part. There is often a "parasitic" draw from one component to another on the same line and that's built into the design of the electrical, so blindly cutting out a part you don't want can often break something else.

If it's too late for that systematic elimination of parts, it will be cheaper in time to get a new harness with all the connections still whole, reconnect everything you can, and work from there. Eliminating parts wholesale is a good way to have a frustrating and ultimately unsuccessful time. If you can't do that, then you must use the wiring diagram to get a better understanding of which components connect to what and which ones are likely necessary. It's likely that all of the connections to the ICM are necessary, even if they don't seem to be. But, that can't be known without a systematic approach or the full engineering diagram from the manufacturer, which is not as easy to come by as the wiring diagram in the service module.

Double-check that this diagram is for your bike, including year and specific model. This is the key component for electrical and there are changes between bikes with relative regularity.

 
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