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Again, that is a closed circuit. Terminology is important.
 

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Discussion Starter #22
That would not be an OPEN, that would be shorted CLOSED.

Overheating of those wires is a common issue in MV Agusta bikes of all models. Loose connections and poor battery voltage create high resistance and high current which creates high hea
look at the values there is nothing
 

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That is because there is no Potential difference (voltage) between the two terminals: ie a closed circuit.
 

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In order to properly test that set of contacts, and rule out a short in the wiring, you need to remove the battery power cable and the ground dable from the solenoid so that it can be "stand alone" tested.

What I see is that you have full continuity through that main set of contacts with the primary coil power removed. That tells me the main contacts are closed in a condition where they should not be closed.

Yes, I would replace the solenoid.
 

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my circuit remains open I can not turn it off with the key and neither turn it on I have to disconnect the 40 amp fuse to turn off the bike
The proper terminology is "The circuit remains CLOSED". An OPEN circuit is disconnected. A CLOSED circuit is connected.

The photos you show are of the STARTER relay....The one the energizes the starter motor. Is your starter motor running continuously ??
The Zero Ohms reading there indicates the starter relay contact are welded closed.
 

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Discussion Starter #28
The proper terminology is "The circuit remains CLOSED". An OPEN circuit is disconnected. A CLOSED circuit is connected.
Yes, if the general relay stays connected (contacts are closed) the bike will remain under electrical power until fuse is removed or battery is disconnected. The key switch activates (closes) the relay.
I would try swapping the relay with known good first.
in any case thank you very much to you for all this information I do not know this bike before I had an aprilia rsv4 thank you thank you !!!!!!!!!!!!
 

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Discussion Starter #29
In order to properly test that set of contacts, and rule out a short in the wiring, you need to remove the battery power cable and the ground dable from the solenoid so that it can be "stand alone" tested.

What I see is that you have full continuity through that main set of contacts with the primary coil power removed. That tells me the main contacts are closed in a condition where they should not be closed.

Yes, I would replace the solenoid.
in any case thank you very much to you for all this information I do not know this bike before I had an aprilia rsv4 thank you thank you
 

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These circuits are the same basic system as any bike...including your Aprillia

I have edited my comments. Read again
 

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Pretty much everything in your bike is ECU controlled. When you turn on the key, the main relay gets power to one side, when the ECU is satisfied, it grounds the other side of the relay plunger activating the power to the rest of the bike.

478338


When you press the START Button, and the ECU is satisfied, the ECU grounds the start relay and power is ported to your starter motor.

478339
 

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Discussion Starter #33
Pretty much everything in your bike is ECU controlled. When you turn on the key, the main relay gets power to one side, when the ECU is satisfied, it grounds the other side of the relay plunger activating the power to the rest of the bike.

View attachment 478334

When you press the START Button, and the ECU is satisfied, the ECu grounds the start relay and power is ported to your starter motor.
View attachment 478335
thank you for all this information you were very knowledgeable
 

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Thanks, I've been down the path with start circuit troubles.
 

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The 40 amp fuse protects the alternator, it's between the alternator and the "B"
terminal on the starter solenoid that's it
More than likely it's the connections in the ignition switch
Remove the 40 amp fuse, key off and short across the solenoid terminals
The motor will crank but not start
I was loaned a General Motors racing Corvette......had the same ignition key problem
it had multiplexed wiring WTF????
Removing 3 fuses would kill the the dash panel, replacing 1 made the key work,
it had headlights, brake lights and running lights
What more do you need?
 

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I maintain my previous diagnosis ... Check the key switch - is it "locked on" regardless of key position ? -- If not, there may be a problem with the ECU, if the Starter solenoid is fused "on" how would you start the bike .. the starter motor would run all the time and drain the battery .. What about the main relay?
 

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I maintain my previous diagnosis ... Check the key switch - is it "locked on" regardless of key position ? -- If not, there may be a problem with the ECU, if the Starter solenoid is fused "on" how would you start the bike .. the starter motor would run all the time and drain the battery .. What about the main relay?
I doubt it is the ECU and still suspect the ignition switch. That switch directly controls power to the ECU, the main relay and the fuel injection relay. Unless there is a hidden circuit, no power should be going though the controlled contacts, if there was it would still require both relays to be stuck closed.
@lounaisse you should try unplugging your key switch and see if the the bike still powers up. You can also check for continuity between terminals 1-2 and 3-4 in the off and on positions.
 

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Discussion Starter #39
In order to properly test that set of contacts, and rule out a short in the wiring, you need to remove the battery power cable and the ground dable from the solenoid so that it can be "stand alone" tested.

What I see is that you have full continuity through that main set of contacts with the primary coil power removed. That tells me the main contacts are closed in a condition where they should not be closed.

Yes, I would replace the solenoid.
Hello
I just saw it is necessary to supply 12v to terminals 1 and 2 to test terminals B and M or is it not worth supplying 1 and 2?
 
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