Parasitic Drain

[J_C]

I've been reading a LOT of threads on this lately, so I tried to follow the right directions... All testing performed with the ignition on lock, key out.

1) I measured the voltage in SERIES from the disconnected battery ground wire to the negative terminal of the battery. 1.1v

2) I began removing fuses, one at a time, until it went away. The voltage went away when I removed the 15A fuse, second from the bottom. As far as I can tell from the wiring diagram, it connects to both the rectifier and the ignition switch.

3) I tried to asses the extent of the drain by turning my multimeter to A-, 200m, and going SERIES to the battery as step one, but I didn't get a reading. I tried moving the multimeter connect lead over to the 10A DC plug as well.

I've imagined two reasons why I am not getting a reading:
a) I'm doing something wrong \\/
b) The multimeter is somewhat broken

In terms of the source of the drain, I'm assuming it either has to be the r/r wire, or the ignition. But if it's the ignition, wouldn't another fuse (namely the 10A one that takes the orange wire from the ignition and puts it out to the engine start switch) also show a voltage reading?


I tried to research, testing, and report to the best of my electrical knowledge. Anybody who could supplement me with additional info would be A+ in my book :-D

[p_s]

I think you'll have an easier time if you disconnect the battery entirely and measure end-to-end resistance. I could see there being a tiny drain through the R/R sense circuitry.

[J_C]

p_s, thank you for the advice. What do you mean by measuring end to end resistance? Do you mean using the multimeter set to Ohms on 200 or 2000, connecting the red and black prongs to each of the battery leads, and reporting back a number? If so, what should this read?

[82Shafty]

I've been reading a LOT of threads on this lately, so I tried to follow the right directions... All testing performed with the ignition on lock, key out.

1) I measured the voltage in parallel from the disconnected battery ground wire to the negative terminal of the battery. 1.1v

2) I began removing fuses, one at a time, until it went away. The voltage went away when I removed the 15A fuse, second from the bottom. As far as I can tell from the wiring diagram, it connects to both the rectifier and the ignition switch.

3) I tried to asses the extent of the drain by turning my multimeter to A-, 200m, and going parallel to the battery as step one, but I didn't get a reading. I tried moving the multimeter connect lead over to the 10A DC plug as well.

I've imagined two reasons why I am not getting a reading:
a) I'm doing something wrong \\/
b) The multimeter is somewhat broken

In terms of the source of the drain, I'm assuming it either has to be the r/r wire, or the ignition. But if it's the ignition, wouldn't another fuse (namely the 10A one that takes the orange wire from the ignition and puts it out to the engine start switch) also show a voltage reading?


I tried to research, testing, and report to the best of my electrical knowledge. Anybody who could supplement me with additional info would be A+ in my book :-D

On of your diodes is probably shot in the reg/rec allowing B+ to trickle to ground. Isolate circuits and you would want to be in series with doing a parasitic test. I have seen bad ignition switches cause the same problem as well and this is why it is very important to perform an "unplug" test.

Quick and easy to unplug the R/R and see if your parasite goes away. I would also unplug the ign switch first to ensure the trigger wire isn't feeding the R/R.

Disconnect the R/R and see if the parasite disappears.

[J_C]

Sorry, I'm a tard. I meant in series, not parallel. Been WAY to long since my science classes :-D But I see what you're saying about disconnecting the switch, and then the r/r. I will go and try in a few mins and report back

[p_s]

p_s, thank you for the advice. What do you mean by measuring end to end resistance? Do you mean using the multimeter set to Ohms on 200 or 2000, connecting the red and black prongs to each of the battery leads, and reporting back a number? If so, what should this read?

Right, disconnect the battery entirely, one probe on each lead, start with teh multimeter set to the highest ohm setting. Should read 1 (or whatever it shows when there is no continuity at all) if there is no leak. But if there's another number, you can divide 12V by that number and it'll tell you how much current you're leaking.

Your 1.1 v reading suggests it's not leaking much. If it's a digital multimeter, it probably has a ~ 10 megaohm impedance in the voltage circuitry, which would put your bikes leakage circuit around 100 megaohms, and you'd be leaking microamps, which is nothing. Maybe come back with a number if this is weird EE greek to you.

[Steve]

Your procedure for step 3 might be OK, but you need to reverse the order. Depending on the meter that you have, you might have separate fuses for the 10A and 200mA current settings. Starting with the 200mA setting might have blown that fuse. If you had a drain large enough to blow the 10A fuse, you would not be calling it 'parasitic'. :shock:

.

[p_s]

All diodes leak a little bit, btw. Probably in the microamp range on 12V.

[chuckycheese]

Anecdotal

This is rather anecdotal but I had a slight parasitic drain a year of 2 back and it turned out to the the R/R itself. I switched it with another one and have had no problems since. By the way, the wiring looked great.8-[

[J_C]

OK, so I probably fried my multimeter. Thats ok, it was cheap.

I can try the resistance reading, however in the meantime I followed 82 Shafty's advice and began disconnecting wires. First I disconnected the ignition switch, no change in the series voltage reading. I then disconnected the red wire from the R/R into the harness, and the drop disappeared.

Here is my wiring diagram: http://www.socal-letsride.com/storag...00L/Wiring.JPG

My thoughts are the following: removing that fuse stopped the drain, and that circuit runs into the ignition and the R/R. Unplugging the ignition did not stop the leak. Unplugging the red wire into the r/r DID. However, this need not indicate the R/R right? Should I have also checked the R/W wire that goes to the starter button? Or am I misreading the direction of the current; Is the R/W just a continuation of the G/W from the stator running through the starter button and INTO the regulator and would have no bearing on a drain? I guess I'm a bit confused here as to how the battery actually gets charged.

[J_C]

This is rather anecdotal but I had a slight parasitic drain a year of 2 back and it turned out to the the R/R itself. I switched it with another one and have had no problems since. By the way, the wiring looked great.8-[

Chucky, I know :-D I was reading your threads last night, looked like boondocks really got you sorted out. You never did post up the resolution though Thanks for filling me in. I think I'm getting to the bottom of this.

[p_s]

The charging output of the RR to the battery is not switched. Solid-state devices like diodes leak almost unmeasurable amounts of current. But if you use the multimeter the wrong way (measuring voltage on an open circuit) you can detect it, which you've done.

[J_C]

I tried the ohms test, but I'm not sure my multimeter is working. The moment I turned it to ohms it read 1. I put red probe to positive lead, black probe to negative lead, with the battery disconnected. I tried all the different ohms settings, they all said 1.

[p_s]

I tried the ohms test, but I'm not sure my multimeter is working. The moment I turned it to ohms it read 1. I put red probe to positive, black probe to negative, with the battery disconnected. I tried all the different ohms settings, they all said 1.

That means there's no leak. (Or actually an infinitesimally small one.) If you turn the switch on, it should read something in the ballpark of 2 ohms if your fuses are all in.

[J_C]

OK that is certainly good news. Thank you for your help. I will keep an eye on the charge of the battery over the next few days to make sure it's not dropping.