Problem: press the starter only get a low audible click no ignition.

Back story:
Today I purchased a new loom for my crashed and stolen recovered k100. It came from a working bike for £15. Bike is not working though

What I'm getting:
I'm getting 12v at the battery.
12v at the green wire for the ignition
12v with the button to ground 86 of the starter relay.

12v at fuse1

Now when I turn the bike on I press the starter button and all I'm getting is a very low noise click. The starter motor isn't engaging at all.

Now before I take the motor off is there any other possible problem it could be?

I'm trying to rule everything out.

Won't let me edit on my mobile I'm also getting 12 volts at the red wire from the ignition.

Since you have a voltmeter put it on the starter motor and check for voltage.  If you've got voltage and the motor isn't running it's the problem.  Make sure your grounds are good.

Thank you kioolt. That was my next port of call. I know I've got good earths already. Is there anything else you could think of?

kioolt wrote:Since you have a voltmeter put it on the starter motor and check for voltage.  If you've got voltage and the motor isn't running it's the problem.  Make sure your grounds are good.

I've checked the starter motor and it's working, did the bench test on it. The grounds are fine.

I removed the fuses to check what voltage I'm getting out of them and got the following in order note only the headlight is connected;

1. 12.4
2. 0.2
3. 12.4
4. 5.4
5. 12.4
6. 12.4
7. 12.4

I'm still getting 12 volts at the battery, 12 volts at the green wire and red wire on the actual ignition. And 12 volts at 86 on the starter relay.

Really not sure where to go from here any advice

Try to ground terminal 85 on the starter relay temporary.
If the starter then turns, the problem is in the ignition ECU or the wiring/connectors
between the starter relay an the ignition ECU.

Have you measured the voltage on the big wires on the starter relay?  I believe they are terminals 30 and 87.  One should be 12 v all the time and the other should have 12 v when pressing the starter button if everything else is ok.

TheJoker wrote:Problem: press the starter only get a low audible click no ignition.

Back story:
Today I purchased a new loom for my crashed and stolen recovered k100. It came from a working bike for £15. Bike is not working though

What I'm getting:
I'm getting 12v at the battery.
12v at the green wire for the ignition
12v with the button to ground 86 of the starter relay.

12v at fuse1

Now when I turn the bike on I press the starter button and all I'm getting is a very low noise click. The starter motor isn't engaging at all.

Now before I take the motor off is there any other possible problem it could be?

I'm trying to rule everything out.

Starting at the top of your original post. 

The low audile click is most likely the starter relay but it could be something else.  By no ignition I'm assuming you really mean that the starter isn't working.  If I'm wrong please let me know.

Are you getting 12v at the battery when pressing the start button?  It's best to check the battery voltage under loaded conditions.

This statement has me a bit confused.  "12v with the button to ground 86 of the starter relay."  Do you mean you have 12 volts measuring from terminal 86 of the starter relay to ground when the button is pressed?


From the way that I am interpreting your description,  I see that the starter relay is clicking when the starter button is pressed but that the starter motor is not turning.  This is one of two things.  The starter relay or the starter itself.  You say you have tested the starter on the bench so that means it is your starter relay.  To test the starter relay measure the voltage on the two little wires when the starter button is pressed.  You should have 12v.  If you have 12 v then next check for 12v on the two big wires on the starter relay.  You should have 12 v on both big wires when the button is pressed and 12 v on only one wire when not.  If the test with the little wires passes and the test with the big wires does not then the starter relay is bad.  If both tests pass then the starter is bad regardless of your bench test.

Further information on the starter relay.  The starter relay needs 12v + from the starter button and a ground from the ignition unit to operate the starter.  Once the engine starts the ground is removed by the ignition unit.

kioolt wrote:Starting at the top of your original post. 

The low audile click is most likely the starter relay but it could be something else.  By no ignition I'm assuming you really mean that the starter isn't working.  If I'm wrong please let me know.

Are you getting 12v at the battery when pressing the start button?  It's best to check the battery voltage under loaded conditions.

This statement has me a bit confused.  "12v with the button to ground 86 of the starter relay."  Do you mean you have 12 volts measuring from terminal 86 of the starter relay to ground when the button is pressed?


From the way that I am interpreting your description,  I see that the starter relay is clicking when the starter button is pressed but that the starter motor is not turning.  This is one of two things.  The starter relay or the starter itself.  You say you have tested the starter on the bench so that means it is your starter relay.  To test the starter relay measure the voltage on the two little wires when the starter button is pressed.  You should have 12v.  If you have 12 v then next check for 12v on the two big wires on the starter relay.  You should have 12 v on both big wires when the button is pressed and 12 v on only one wire when not.  If the test with the little wires passes and the test with the big wires does not then the starter relay is bad.  If both tests pass then the starter is bad regardless of your bench test.

Further information on the starter relay.  The starter relay needs 12v + from the starter button and a ground from the ignition unit to operate the starter.  Once the engine starts the ground is removed by the ignition unit.

By no ignition means that when I press the button I get nothing, no dimming of the headlight. No audible noise; nothing.

When I press the button I'm still getting 12v, I've checked another battery as well and it results in the same.


"12v with the button to ground 86 of the starter relay."     This means that someone told me to try with the power turned on so the neutral light is showing check that terminal 86 is getting 12v I checked as well with the button pressed and got the same result.

I was getting a low audible click when I turn the key to the on position and pressed the button; but now I'm not getting it when I press the starter button. I checked the starter motor on the bench using jump leads to the battery and it turned. So the starter motor is actually working.

I will check the starter relay tomorrow.

Hi, I'm new here from Wild Guzzi, I must say the standard of Electrical help is very high.
I found an excellent document by Bertrand Vogel "EFI/Electronic Ignition K100 2V Troubleshooting", this should be in every-ones tool box.

Have you tried jumpering out the two large terminals of the Start Relay, that will prove out the battery, wiring and starter (make sure the bike is in Neutral first), use a heavy wire #12 or larger. 

If you unplug the start relay you should see 12V across 85 - 86 of the connector with the button pushed.
If not monitor each point to ground as you push the button (with the relay in if you can)

Well I was having problems still so I tried jumping the starter motor (live wire straight from the battery to the starter motor) with it attached to the bike and got nothing pulled the plugs, to be honest it was one thing I know I should have checked but just didn't. Then tried jumping with the starter motor again and got the bike cranking.

Didn't get the bike started but there isn't that much fuel in the tank. So I'm thinking that it could possibly be something to do with the wire linking the starter motor to the starter button. Or something else. I'm getting another parts bike though which is of the same year as mine. Mostly intact with a running engine. So should give me something to play about with.

TheJoker wrote: 

Didn't get the bike started but there isn't that much fuel in the tank. So I'm thinking that it could possibly be something to do with the wire linking the starter motor to the starter button. Or something else. I'm getting another parts bike though which is of the same year as mine. Mostly intact with a running engine. So should give me something to play about with.

When you jumper the starter it may not start because the Ignition module won't pick up the Fuel Injection Relay (I may be wrong, I'm new here) to start the pump and fire the injectors,
Jumpering around the Start Relay was just to prove the battery and starter motor are ok, those you can rule out now.
Bertrand Vogel's excellent document shows a simple schematic and table on page 19.
On page 16 it shows
Power comes from the battery, (thru the ign switch not shown), thru the kill switch, thru a fuse, thru the clutch switch, to the Start button, from button to the relay, If you don't have a multimeter solder a couple of wires on a small 12 Volt lamp and use that to trace the power flow, one wire connected to the chassis.
If you have a meter measure the resistance of the start relay coil, I have no idea what it should read but less than 100 Ohms is my guess.
Be sure to test your lamp before starting by connecting it across the battery

If you get as far as the start relay and you still get 12 Volts with the button pressed it could be the Ignition module is not holding pin 11 at ground, I would measure that with a volt meter.

Just reading back in the thread you said you had 12 Volts at 86 of the start relay, just to be certain can you check that at the Ignition Module pin 11 with the key on button pushed?

Kiwi_Roy wrote:
......

Bertrand Vogel's excellent document shows a simple schematic and table on page 19.
On page 16 it shows
Power comes from the battery, (thru the ign switch not shown), thru the kill switch, thru a fuse, thru the clutch switch, to the Start button, from button to the relay, If you don't have a multimeter solder a couple of wires on a small 12 Volt lamp and use that to trace the power flow, one wire connected to the chassis.
If you have a meter measure the resistance of the start relay coil, I have no idea what it should read but less than 100 Ohms is my guess.
Be sure to test your lamp before starting by connecting it across the battery

.......

Bert (Crazyfrog) is our esteemed Overlord and Creator and all his work is hosted or linked in this site off the Portal page. A lot of it is in the members only section.
Re soldering wires to a 12v bulp.... Just run down to your local auto parts shop or even a $2 shop and buy a circuit tester for about $5.

Kaptain, I'm certainly not questioning your electrical prowess, but I was led to believe that those circuit testers are not to be used on our bikes.
An LED type is preferred?

A circuit test like that is ok working on the starter circuits.  It's when you're working with the Hall sensors that you don't want to use that kind of tester.

Thanks for the clarification kioolt.

kioolt wrote:A circuit test like that is ok working on the starter circuits.  It's when you're working with the Hall sensors that you don't want to use that kind of tester.

Spot on Kioolt that is why I recommend to get into the habit of using an LED test light on any electrical circuit and preferably a digital multi meter.