Parasitic draw with ANY regulator

[tkocher92]

Good Evening,

I have an interesting problem here that is not easy to pin point.

When metering the negative post on the battery to its respective, unconnected terminal (leakage test), there is a constant 12+v parasitic drain on my battery as long as there is a regulator rectifier plugged in.

It does not matter which regulator, I have tried 2 healthy ones that have the same connectors, and have tested one different but healthy rr using alligator clamps. All are giving me the same reading.

if I unplug the rr from the harness, the voltage reading drops down to about .20~ volts.

The amperage reading remains at zero, although it does read 12+ Volts.

[hillsy]

The RR connects directly to the battery - it is fused but not on a switchable circuit.

I'm not sure what connectors you are checking, but if there is no current draw then there is no parasitic draw for that circuit.

[tkocher92]

Voltage regulator plugged in: unhook negative terminal, place multimeter (+) probe on batteries positive post, and (-) probe on disconnected negative battery terminal. Voltage Reads 12v

Voltage regulator unhooked from wiring harness. same test reads 0 volts.

Wash and repeat with the same regulator off a running and charging bike with no draw, same results.

[WintrSol]

Voltage regulator plugged in: unhook negative terminal, place multimeter (+) probe on batteries positive post, and (-) probe on disconnected negative battery terminal. Voltage Reads 12v

Voltage regulator unhooked from wiring harness. same test reads 0 volts.

Wash and repeat with the same regulator off a running and charging bike with no draw, same results.

None of that makes sense. Are you measuring directly across the battery, from (+) to (-)? This should always read battery Voltage no matter what is connected, and disconnecting the battery (-) cable should change nothing. Did you lower the battery so you could measure directly across its terminals, or are you attempting to measure it through the terminal access openings?

To properly measure a drain, make sure there is no connection to the battery negative terminal, then connect the meter in Amps mode between the battery negative and the disconnected cable; with all systems off, there should be no current, but start on the highest Amp setting of the meter, just to be safe.

[tkocher92]

Yes that is what I am doing.

it reads 0 amps, and 12.26 volts

[WintrSol]

Yes that is what I am doing.

it reads 0 amps, and 12.26 volts

So, the battery reads 12.26V across the terminals, and reading from the battery negative terminal to the negative cable is 0A? So, no parasitic load is present. Why are you looking for one? BTW, 12.26V is a fairly low state of charge, and if it doesn't stay above that after charging, the battery is failing. Fresh of a low-current charger (1.5A or less) it should settle to about 12.8V, and not go below 12.6V after some time, with no load. If it continues dropping from there, you need a new battery.

[tkocher92]

no not at all I don't know where you keep getting that Im reading across the terminals.

I am doing the test you are describing in your post and ONLY that test. I am testing for a parasitic draw/voltage leak/ drain on the battery. and only that. I know I am using a good battery, I do not need to test its voltage, I know what it is.

Now, when I am doing the test you described, I am getting a reading of 0 amps. KEEPING THE PROBE LEADS IN THE SAME POSITIONS, all I am doing is switching my meter from amps to voltage, (and switching the black probe going into the meter from AMPS to COM), and I am reading 12 volts. IF I unplug the regulator during this test, the voltage reading drops to about .25.

[WintrSol]

no not at all I don't know where you keep getting that Im reading across the terminals.

OK, first you said you measured from the negative battery terminal to the cable disconnected from that terminal, and got 12V. That would suggest there is leakage from the battery positive to chassis ground, which could be normal, as all electronic devices have some very small leakage current, usually in the micro amps (much below what most common Amp meters can measure). You also said you disconnected the regulator, and that measurement dropped to 0V; since the regulator is the only electronic device connected that could have some leakage, that would also be normal.

In your second post, you said you measured from the positive battery terminal to the cable that was disconnected from the negative terminal, and got a reading of 12V, which implies there is a path to the negative battery terminal around the disconnected cable. Or, you misstated which battery terminal you used.

I am doing the test you are describing in your post and ONLY that test. I am testing for a parasitic draw/voltage leak/ drain on the battery. and only that. I know I am using a good battery, I do not need to test its voltage, I know what it is.

Now, when I am doing the test you described, I am getting a reading of 0 amps. KEEPING THE PROBE LEADS IN THE SAME POSITIONS, all I am doing is switching my meter from amps to voltage, (and switching the black probe going into the meter from AMPS to COM), and I am reading 12 volts. IF I unplug the regulator during this test, the voltage reading drops to about .25.

When reading Amps, one probe should be connected to Amps, the other to COM; if the one not connected to COM is connected to the V input, you will not get a current reading. What I'm saying is, one probe should always be connected to COM, for both Voltage AND Amps. In any case, if the stray Voltage you are measuring is due to leakage current, you will still not measure any current, as the current should be too low to measure.

OTOH, if you connect your meter properly and get a meaningful current reading, you DO have a parasitic loss, and need to find it. Your user name implies you have a '92, which has a separate Voltage reference wire from the key switch to the regulator, so the regulators Voltage control does not leak current when the key is off. Later models removed this input the the regulator; apparently, upgraded to the regulator reduced the measurement current that they didn't feel switching it was needed. In any case, if someone has changed this wire to bypass the key switch, that could be your leak.

[tkocher92]

Very informative thank you, I will test it out again and report back. I could be chasing nothing...

[WintrSol]

Do you have a problem with the battery going flat in a few weeks, or just checking out of curiosity?