- Joined
- Apr 25, 2005
- Messages
- 68
- Location
- ohio USA
I have been a member on this sight for a couple of months and have learned a great deal from many helpful people. I seek knowledge the same as everyone else here. The problem; I feel, is we all want fast easy solutions to our problems. That is one of the great benefits of this sight! We hope that when we start a new post, that someone with the exact same bike has been there before us, and has ran into that problem already, and has a solution. A lot of time this works well and other times it does not. I am putting this here for those of you who would like to have a reference on how to go about electrical troubleshooting. Husabergs are prone to electrical gremlins, and with a little knowledge under our belt, we can find the root cause sooner while being less frustrated. I cannot contribute too much with Husaberg specifics, as I'm still green. But I can help in the area of electrical diagnosis. So I hope this helps someone.
1st. Resistance tells you nothing about the quality of a wire.
While checking a wire for resistance, the meter is set to read Ohms. The test has the person put the meter leads at each end of the wire. A reading clostest to 0.00 is better. The meter actually pushes a little voltage from its onboard battery through the wire and looks at what the other lead sees. The meter knows how much voltage it put out and knows how much came back and calculates the resistance to that flow. The problem with this is that the meter is putting through microamps. If I was testing a battery cable that has 50 Amps going through it when cranking, the above test would mislead you even if the meter read very low resistance. If we rely on resistance testing, we are saying if the wire didn't fail while pushing microamps through it, then it will be fine when we pass 50 Amps through it.
2nd. Checking for voltage tells you nothing about the quality of the wire.
This test has the meter set to voltage and the user will connect the red lead to anywhere that there should be voltage and the black one to a good ground. If the user of the meter sees voltage present and the number is good, such as 13 Volts, they move on to something else.
Checking for the presents of voltage is not good enough. One must see how much the voltage holds up while that circuit is actually being used or attempting to be used.
Picture that I took a brand new battery cable and I stripped back the insulation in the middle. I then cut all of the individual strands of copper except for one! I then taped it up so that you couldn't tell. I then asked you to check the resistance of that wire and tell me if it is good. The reading would tell you it was a good battery cable. Then I asked you to check the voltage on that wire. Your reading would be the same, good. You would see the exact same battery voltage on that wire!
So lets recap... The resistance readings would be excellent, telling you the wire was good.
The voltage readings would be excellent, telling you the wire was good.
So what would happen when we put that "good" wire in the starting circuit and hit the starter button?
Would the bike crank? Or would the wire go up in smoke?
I hope you get my point.
If a different approach was taken, the bad wire would be found.
Voltage drop testing:
Understanding voltage drop testing requires a look at how a meter works. A digital volt ohm meter or DVOM subtracts the lower number from the higher number. What I mean by this is if the red lead sees 12 volts and the black lead sees 0 volts, then it subtracts the 0 from the 12 to get 12.
But what if the red lead sees 12V and the black lead sees 6V? The meter will read 6 V. 12 - 6=12. This is the very principle that is utilized in voltage drop testing.
If the bad wire from above was installed on a motorcycle between the battery solenoid and the starter, we could use voltage drop testing to determine if it is good or not. We are going to set-it-up-to-fail. Relying on The fact that the meter subtracts the lower number from the higher, and we know that the voltage on a good battery cable should have the same voltage at the battery end as the starter end while cranking, we can redo this test and see how well the cable can keep the voltage from dropping before it reaches the starter. Put the red meter lead on the beginning of the wire and the black meter lead at the other end of that same wire which would be at the starter. With the meter set to DC Volts, attempt to crank the bike. The meter will display the amount of lesser voltage at the starter end. Anything more than .2 VDC indicates a problem with the wire or its connections. This test can be repeated anywhere on the bike and with any circuit. If we did this test to the bad wire as mentioned above, it would have fallen flat on its face, even though the resistance check was good and the voltage check was good. The reading would have been something like 10 or 12 volts. This means that the black lead saw 10 to 12 less volts than the red one did. I hope this is useable to you all and remember you can use this anywhere on the bike. Just take the above example and apply it to all circuits.
Hope this helps!
Volvonut
1st. Resistance tells you nothing about the quality of a wire.
While checking a wire for resistance, the meter is set to read Ohms. The test has the person put the meter leads at each end of the wire. A reading clostest to 0.00 is better. The meter actually pushes a little voltage from its onboard battery through the wire and looks at what the other lead sees. The meter knows how much voltage it put out and knows how much came back and calculates the resistance to that flow. The problem with this is that the meter is putting through microamps. If I was testing a battery cable that has 50 Amps going through it when cranking, the above test would mislead you even if the meter read very low resistance. If we rely on resistance testing, we are saying if the wire didn't fail while pushing microamps through it, then it will be fine when we pass 50 Amps through it.
2nd. Checking for voltage tells you nothing about the quality of the wire.
This test has the meter set to voltage and the user will connect the red lead to anywhere that there should be voltage and the black one to a good ground. If the user of the meter sees voltage present and the number is good, such as 13 Volts, they move on to something else.
Checking for the presents of voltage is not good enough. One must see how much the voltage holds up while that circuit is actually being used or attempting to be used.
Picture that I took a brand new battery cable and I stripped back the insulation in the middle. I then cut all of the individual strands of copper except for one! I then taped it up so that you couldn't tell. I then asked you to check the resistance of that wire and tell me if it is good. The reading would tell you it was a good battery cable. Then I asked you to check the voltage on that wire. Your reading would be the same, good. You would see the exact same battery voltage on that wire!
So lets recap... The resistance readings would be excellent, telling you the wire was good.
The voltage readings would be excellent, telling you the wire was good.
So what would happen when we put that "good" wire in the starting circuit and hit the starter button?
Would the bike crank? Or would the wire go up in smoke?
I hope you get my point.
If a different approach was taken, the bad wire would be found.
Voltage drop testing:
Understanding voltage drop testing requires a look at how a meter works. A digital volt ohm meter or DVOM subtracts the lower number from the higher number. What I mean by this is if the red lead sees 12 volts and the black lead sees 0 volts, then it subtracts the 0 from the 12 to get 12.
But what if the red lead sees 12V and the black lead sees 6V? The meter will read 6 V. 12 - 6=12. This is the very principle that is utilized in voltage drop testing.
If the bad wire from above was installed on a motorcycle between the battery solenoid and the starter, we could use voltage drop testing to determine if it is good or not. We are going to set-it-up-to-fail. Relying on The fact that the meter subtracts the lower number from the higher, and we know that the voltage on a good battery cable should have the same voltage at the battery end as the starter end while cranking, we can redo this test and see how well the cable can keep the voltage from dropping before it reaches the starter. Put the red meter lead on the beginning of the wire and the black meter lead at the other end of that same wire which would be at the starter. With the meter set to DC Volts, attempt to crank the bike. The meter will display the amount of lesser voltage at the starter end. Anything more than .2 VDC indicates a problem with the wire or its connections. This test can be repeated anywhere on the bike and with any circuit. If we did this test to the bad wire as mentioned above, it would have fallen flat on its face, even though the resistance check was good and the voltage check was good. The reading would have been something like 10 or 12 volts. This means that the black lead saw 10 to 12 less volts than the red one did. I hope this is useable to you all and remember you can use this anywhere on the bike. Just take the above example and apply it to all circuits.
Hope this helps!
Volvonut
