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Discussion Starter #1 (Edited)
I decided that after 9 months or ignoring it, I would learn to use a multimeter and add that to my maintenance skilz.

Item #1
I watched a few YouTube videos, and decided to try to the parasitic draw test by setting the MM to 20v, disconnect the negative from the battery and then make the jump between the cable and the negative terminal through the MM - the load was about 12.5. So then I pulled fuses one by one with no changes until I pulled the master in the fuse box below the ECU. At that point the load dropped to 1.5. That indicates one of 9 things per the workshop manual injector connectors, horn, cluster, immo, kickstand switch...

I then narrowed it down to disconnecting the cluster plug at the cluster and found that this was the draw.

Is that normal? I mean I guess it has to maintain some draw to keep track of a few things - but want to be sure that it's not an issue.

Item #2
Next up was a continuity issue I may have found. I've had some tail harness issues showing periodically, so I went into continuity mode on the MM and went at it.

I have a SupaBrake by ViziTec in the tail for higher visibility taillight blinking. There are three in wires and three out wires. Two of the wires showed good continuity, while the red on showed no continuity at all (testing just before and just after the device.

Is this just a part of the circuit design for that type of device, or is there an issue with my SupaBrake?

As always, TIA!
 

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2001 900SSie
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Not correct.

There are three common things that a multimeter (MM) is used to measure, being voltage, resistance and current.

For fault finding on a bike you will typically be measuring voltage and resistance. The only time I have ever measured current on my bike was to see what minuscule current the ECU was drawing when the bike is completely off.

When you did Item #1 you did not have the MM on the correct setting. Here you should have been measuring current, not voltage.
To measure current flowing in a wire the multimeter has to be in line with the wire.
For this item you would disconnect the positive lead to the battery.
Switch the MM to DC Amps then connect the red MM probe to battery positive and the black probe to the positive lead of the harness.
This will then show the current flowing through the MM connected in line.
When measuring current it is important to have a feel for how much will flow, as if the current is higher than the scale on the MM you selected, it will blow the fuse inside the MM. I would start on the highest setting to see what is flowing, then reduce the scale to that above the current measured for maximum accuracy.
All three MM I have have a separate positive lead position (socket) on the meter for measuring current. One is a flashy auto ranging MM and only has one socket. The other two have a 2 Amp socket and one has a 10 A socket and the other has 20A.
If the current you are measuring is higher than the socket rating, then you will blow the protection fuse.

Item #2 - here you are measuring resistance. Make sure the MM is on the resistance scale.Here you connect red MM probe to one end of a cable or in your case lamp and the other probe at the other end of the cable or side of the lamp. You can safely elect any resistance scale, then change the scale selector to get the maximum accuracy reading.
Typically on a bike you are looking for (hoping for) low resistance, otherwise you have a broken wire or corrosion related resistance.
The resistance scale is also used for measuring coil, injector, temperature sensors etc. that have specified resistances or resistance ranges when functioning correctly.

EDIT - a good example of measuring resistance is the side/kick stand switch. Disconnect it, then on the lowest resistance scale, put the MM probes into the switch side of the connector. Stand down resistance is infinite, usually shown as OL. Stand up and resistance should be essentially zero.
Note, the switch usually has three pins, so you will need to work out which two are used for the ECU. Usually there is a common wire and resistance to one terminal is invite and the other zero. These then flip to zero and infinite when the stand is moved from down to up.

I am not familiar with the light unit you have installed. Typically a rear light, well at least on mine, has a bulb with two filaments. One for brake and the other is the tail light. There is a common negative, the bulb's metal body. There should be resistance from each filament between the filament contact and the bulb body.
For you unit it may be LED ?? If so, then polarity of the MM probes is important, as it will show a resistance when the probes are connected one way, but if you swap them over you will probably see invite or extremely high resistance.

Voltage measurements are the simplest. On a bike put the MM on the 20 Volts DC range and connect the red probe to the most positive point and the black to the most negative. You will not harm the MM if you connect the probes the wrong way around as the MM will show negative voltage.

As an example, if you wanted to test if voltage is getting through to a coil, connect the red probe to the positive connector in the coil and the black probe to battery minus. At key on, during the period the pump is priming, you should see battery voltage or thereabouts on the meter.

EDIT - I just had a look at the SupaBrake. It has 3 wires in from the harness and 3 out to the bulb.
One wire will be the common negative and from one side of the unit to the other will be zero resistance.
The same will apply to the wire in/out for the tail light.
The brake light wires will be different as the unit contains electronics to flash the brake light. The electronics between in and out here will affect resistance, as will polarity of the MM probes. Red probe will be on the harness side of the unit and black on the bulb side. Not sure what resistance you would measure though.
 

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Discussion Starter #3
Thanks

Not correct.

There are three common things that a multimeter (MM) is used to measure, being voltage, resistance and current.

For fault finding on a bike you will typically be measuring voltage and resistance. The only time I have ever measured current on my bike was to see what minuscule current the ECU was drawing when the bike is completely off.

When you did Item #1 you did not have the MM on the correct setting. Here you should have been measuring current, not voltage.
To measure current flowing in a wire the multimeter has to be in line with the wire.
For this item you would disconnect the positive lead to the battery.
Switch the MM to DC Amps then connect the red MM probe to battery positive and the black probe to the positive lead of the harness.
This will then show the current flowing through the MM connected in line.
When measuring current it is important to have a feel for how much will flow, as if the current is higher than the scale on the MM you selected, it will blow the fuse inside the MM. I would start on the highest setting to see what is flowing, then reduce the scale to that above the current measured for maximum accuracy.
All three MM I have have a separate positive lead position (socket) on the meter for measuring current. One is a flashy auto ranging MM and only has one socket. The other two have a 2 Amp socket and one has a 10 A socket and the other has 20A.
If the current you are measuring is higher than the socket rating, then you will blow the protection fuse.

Item #2 - here you are measuring resistance. Make sure the MM is on the resistance scale.Here you connect red MM probe to one end of a cable or in your case lamp and the other probe at the other end of the cable or side of the lamp. You can safely elect any resistance scale, then change the scale selector to get the maximum accuracy reading.
Typically on a bike you are looking for (hoping for) low resistance, otherwise you have a broken wire or corrosion related resistance.
The resistance scale is also used for measuring coil, injector, temperature sensors etc. that have specified resistances or resistance ranges when functioning correctly.

EDIT - a good example of measuring resistance is the side/kick stand switch. Disconnect it, then on the lowest resistance scale, put the MM probes into the switch side of the connector. Stand down resistance is infinite, usually shown as OL. Stand up and resistance should be essentially zero.
Note, the switch usually has three pins, so you will need to work out which two are used for the ECU. Usually there is a common wire and resistance to one terminal is invite and the other zero. These then flip to zero and infinite when the stand is moved from down to up.

I am not familiar with the light unit you have installed. Typically a rear light, well at least on mine, has a bulb with two filaments. One for brake and the other is the tail light. There is a common negative, the bulb's metal body. There should be resistance from each filament between the filament contact and the bulb body.
For you unit it may be LED ?? If so, then polarity of the MM probes is important, as it will show a resistance when the probes are connected one way, but if you swap them over you will probably see invite or extremely high resistance.

Voltage measurements are the simplest. On a bike put the MM on the 20 Volts DC range and connect the red probe to the most positive point and the black to the most negative. You will not harm the MM if you connect the probes the wrong way around as the MM will show negative voltage.

As an example, if you wanted to test if voltage is getting through to a coil, connect the red probe to the positive connector in the coil and the black probe to battery minus. At key on, during the period the pump is priming, you should see battery voltage or thereabouts on the meter.

EDIT - I just had a look at the SupaBrake. It has 3 wires in from the harness and 3 out to the bulb.
One wire will be the common negative and from one side of the unit to the other will be zero resistance.
The same will apply to the wire in/out for the tail light.
The brake light wires will be different as the unit contains electronics to flash the brake light. The electronics between in and out here will affect resistance, as will polarity of the MM probes. Red probe will be on the harness side of the unit and black on the bulb side. Not sure what resistance you would measure though.
Thanks Punch. I'm going to read this a few times :)
 

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2001 900SSie
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Thanks Punch. I'm going to read this a few times :)
Now worries. It is just a matter of knowing what you want to measure, where to measure it and selecting the correct units and scale on the MM.
 

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6mA constant is enough to kill a battery. usually 1.5 or so due to ecu, spiking to 10mA or so with the immo light on the dash.

pulling fuses is a good way to indicate a fault when reading current. pulling the master fuse usually fixes most things, because nothing is connected.
 
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