1982 XJ550 Starter Circuit Issues

Hey guys,
It's me again. I resurfaced the clutch plates and threw in new springs while I was waiting for some carburetor parts. That quelled the mechanical itch a little bit. I still have not been able to perform a compression test. I bought a new battery and got it charged up but I cannot seem to get the bike to turn over at all. I have used a multimeter to follow through with the suggestions in this thread: How to: Ignition troubleshooting.
It seems that with the key in the ignition I have around 12 volts. Pressing the starter button gets no audible reaction, however the voltage does drop to around 10. I did not check the safety relay resistance (black and white wire from TCI) as this wire is cut, capped, and zip tied. The bike is in neutral with the kickstand down. Neutral light is on. I am unsure how important this is with the snipped wire. I do not know a ton about electronics, maybe this itself is the issue. I have read on here that it is unwise to disable these safety features and I will likely rewire them if the bike passes the compression check.

I was curious if the advice given in the aforementioned thread would be good for me to follow; finding a new TCI. I also thought that perhaps my issuer lies in the actual starter motor or the solenoid. Advice on which component to look into first would be appreciated.

 

Just put 12 volts to the solenoid crank wire,if it cranks over then you can be sure that the starter motor is okay then,unless the motor is seized,then you will need to turn the motor over by hand by removing the small round timing cover on the left side of the bike and turning it over with a wench by hand.If all of the above is in order then its back to voltage checks,grounds,voltage drops.
Electronics and 12 volt electrical theory are two different classes.

 

There you go. Just be careful, as you will probably generate a few sparks but I wholly agree. Jump 12V to the starter and see if it spins. The voltage drop when the button is mashed and no accompanying "click" anywhere could be a failed relay but is more likely a wiring problem. Quickest way to eliminate the safety circuits for troubleshooting is to simply unplug the safety relay.

As for the compression test and any further troubleshooting: don't spin the motor over with the spark plugs removed or disconnected without unplugging the TCI unit first. The TCI can be damaged trying to fire plugs that aren't there. A couple of the manuals recommend grounding the plug leads, but simply unplugging the TCI unit is easier and more reliable. You're going to need to get the motor to spin via the starter, you cannot get a good compression test turning it by hand. (Plus you're gonna want to start it eventually.)

(The TCI unit has nothing to do with not being able to get the bike to turn over via the starter.)

 

So I jumped the solenoid and it engages the starter motor. Which in turn did its job and cranked the engine. Any pointers on where to go now with this information? Or is it just sort of a methodical testing of all the wiring in the starter circuit?

Removed the safety relay to see if that made a difference. It did not.

Thanks again guys!

 

See, you've already begun your troubleshooting: you now know that the starter works; and you now know that it is not an issue with the safety circuits (at least at this point) so it has been narrowed down considerably. Leave the safety relay unplugged for now. Also, by jumping the solenoid, you've verified the wiring between it and the starter. In addition, since you're not getting a response at all (no click) from pressing the starter button, tracking down the problem should be relatively easy at this point. Which manual/wiring diagram(s) are you using?

 

If you unplug the starter solenoid from the harness you can apply 12 volts to the coil and see if the solenoid is working. If it is, then the problem lies somewhere on the starter-button side of the system. You can isolate the starter button by unplugging it (the plug is in the headlight housing) and using a jumper wire to the harness plug to see if it's a fault with the switch or a fault in the harness or relay.

 

the plug from the starter control connects to the main harness just under the right ignition coil. you will have to remove the tank to get to it.
there will be 2 red/white wires which run up to the run/kill switch in main harness and control connector
there is a blue/white wire which runs to the starter button from the solinoid it is in both connectors.
there is a black wire running back from control a ground wire but there is no mating connection in the main harness connector. the right control grounds through the handle bars so the bars must be chrome not painted.
the wire restraint on the control must be cleaned it makes the ground connection as well as the circumfrence of the hole that the bar passes through.

if when you press the starter button your oil light lights up,, the starter button is grounding if bulb does not light up you have no ground or a bad bulb.

unplug solinoid and at harness connector hook volt meter or test bulb to battery ground and to red/white wire with key on, test bulb should light up or you get a 12 volt reading on meter.
if when testing the red white wire you did not get 12 volts look at fuse and kill/run switch as the issue


hook meter or test bulb to positive of battery and to blue/white wire press starter button you should get 12 volts or bulb lights up this confirms the starter button is working/making ground.
if the second test does not give you the expected results starter button may need to be cleaned or replaced.
you can add a ground wire to the control wire ground.
add a wire at connector end of control harness and run it to ignition coil mounting bolt use a ring terminal. splice the new ground to connector ground to complete.
or you can order pin for main harness connector and run wire from that for a quality look.

another test for bad ground is hook a clip lead to battery negitive and use a ring terminal to connect to screw that holds control onto bars. this will establish a ground for the starter button

 

FYI the starter button tests the oil light bulb when you press it.
when you change your oil turn on key and oil light should come on this will indicate that the oil level switch is working.

 

And if you have a multimeter you won't need to unplug the starter switch to test it. You can just check for continuity with teh button pressed when you unplug the solenoid from the harness. Check on the harness plug.

 

See, I told you I'm getting old. Completely forgot about ground for the switch pod relying on the handlebar for its connection. Sorry it took so long to ask: does this bike have the original chrome handlebar? Is the RH switch pod the original Yamaha one?