1980 gs1100 - diode test for regulator - charging ISSUES

[hotdergs07]

After a little work with my multimeter I have located the fault in my charging system...I think. At www.thegsresources.com i found a trouble tree chart for charging system diagnosis. Everything passed performance test but my rectifier/regulator, but it is BRAND NEW. I am performing a diode test with my multimeter and not getting expected results, anybody have suggestions for RR testing?? Thanks

[Redman]

ANy further update?

What tests did you do that seemed okay?

Does your meter have the diode test feature?

[hotdergs07]

ANy further update?

What tests did you do that seemed okay?

Does your meter have the diode test feature?

Update.
I've got low to no charging voltage at Idle- anywhere from 12.8-13.1 V. None at higher RPM's.
No voltage drop on the power and grounds at the R/R. S
tator resistance was all O.K. .5-2.0 ohms.
No short from stator to engine casing and I am getting around 68-73 V AC coming out of stator coils.

The diode testing is where the R/R fails. The stock rectifier-I was told-was heating up excessively and blowing fuses...I bought a new aftermarket one and STILL, a no to low charge problem is still occuring. I am worried that this is either the wrong part or came from the factory faulty. The problem occurs at this step: Connect the RED multimeter lead to the RED positive output wire of the RR. Connect the BLACK multimeter-lead to one of the yellow wires. I Should be getting 1.5 V or higher but im not getting any reading at all. However, at this step: Connect the BLACK multimeter lead to the RED output wire of the RR. Connect the RED multimeter lead to one yellow wire. Check the reading. Repeat this procedure for the two other yellow wires. I am getting passing readings of .567 V. It is the same process with the next two steps, for some reason I am not getting the 1.5 V readings but I AM getting .50 V readings on the appropriate tests.

Am I performing the tests wrong or should I just try a different brand of R/R? I have heard things about using honda RR's too, what would be the cheapest?

[Steve]

Does your multimeter have a "diode test" function on it? It makes a difference. Sometimes just checking the resisitance will work, but a diode test function will actually put out enough voltage to turn on a diode to check it. Please also note that these checks are to be done with the regulator unplugged from the bike. It does not have to be removed, just unplugged.

I have not looked at the exact wording of the test you are trying to do, but the concept is to put one color lead (let's say RED for this test) on the red output wire, and the other lead on each of the three yellow input wires. You should get about the same reading for each leg, and it should show a very high (basically infinite or "OL") reading. Now put the BLACK lead on the red output wire and do the same test. Again, you should get similar readings, but they should show about .5 volts.

Now do the same tests, but put the BLACK meter lead on the black ground wire from the regulator and the RED meter lead to each of the three yellow input wires. With the black meter lead on the black wire, readings will be high, with the red meter lead on the black wire, readings will be about .5 volts.

When it is all checked out, make sure the black lead from the regualtor had a GOOD ground. Don't just bolt it down to the regulator mount, run another wire from that mount up to the battery. When the regulator is trying to regulate, it shunts the excess current to ground, so it needs a GOOD path to follow.

If none of this checks out, contact your source for the regulator to see if there was any warranty. If not, you can spend the money for another new one, or take your chances on a used Honda unit from eBay. If you get a good one from eBay, you will be good to go. By the way, I have not gotten a bad one yet, and I have bought 4 or 5 for various bikes.


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[SqDancerLynn1]

68-73 V AC coming out of stator coils. Is that on all three leads at 5K rpm ? The reg test can tell you if it is shorted but does not give it an acurate working test. If the stator us good & wiring is good you probably got a bad reg

[hotdergs07]

Does your multimeter have a "diode test" function on it? It makes a difference. Sometimes just checking the resisitance will work, but a diode test function will actually put out enough voltage to turn on a diode to check it. Please also note that these checks are to be done with the regulator unplugged from the bike. It does not have to be removed, just unplugged.



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Yeah I have the diode function, I have a newer snap on DMM. I did get OL for the first three and about .5 V for the other. So i think I am good. I will try running the ground wire directly to the battery and see what happens. But if the direct ground still doesn't resolve my problem. What direction should I go? My battery light is still on and it won't charge...

Is there any other wiring I should check besides power and ground volage drop at the regulator???

[Steve]

Not sure about the battery light on a GS, but on my son's Yamaha Venture Royale, and my Kawasaki Voyager, the battery light was an indicator for low fluid in the battery, not a charge indicator.

Now...if your fluid IS low, you may not be showing much of a charge anyway.

Anyone else out there know the function of a GS's battery light?


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[hotdergs07]

battery light/no charge diagnosis at a DEAD END??

Not sure about the battery light on a GS, but on my son's Yamaha Venture Royale, and my Kawasaki Voyager, the battery light was an indicator for low fluid in the battery, not a charge indicator.

Anyone else out there know the function of a GS's battery light?


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Battery is good, just bought it last summer and kept it on the trickle charger/maintainer all winter long. I tried giving the rectifier a jumper to battery ground and still no improvements in the charging system performance...

I'm getting like 13.0-13.5 volts at idle (a pretty good reading), but anything above 2500 RPM is 12.7 and below. And this battery light is DRIVING ME CRAZY. What now? Everything passed the tests, the battery is brand new...what gives?

[hotdergs07]

New Ideas

Found out that the battery light is a fluid level sensor, and my aftermarkey battery doesn't have a sensor, so im just going to unplug the dash light and call it a day for that.

As far as the charging system, I think im going to take apart my stator/rotor assembly when I go home this weekend, I don't know exactly how the rotor is driven but I have reason to believe that whatever is driving it may be slipping causing no charging volts at high RPM but some lower volts at idle. Any other advice is appreciate, especially knowledge of what drives the rotor/stator.

It's got to be either a slipping rotor/stator OR an extreme electricl draw somewhere on the bike...I shall bring home my rusty amp clamp to test this as well.

[Steve]

The stator should be firmly bolted to the engine cover, and not move. If it does move, the wires won't let it go very far.

The rotor should be firmly attached to the end of the crank. It is actually part of (if not all of) the flywheel.

Depending on how hard it might be to disconnect your battery light inside the gauge cluster, it might be easier to attach the sensor to the + side of the battery. Normally, it sits in the battery acid, so it has a small voltage applied to it, unless the water level is low. Your new battery does not have that access port, so just jumper it to +12 volts somewhere.


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[Hap Call]

I would contact the manufacturer of the regulator. If the voltage of the stator between phases is 80V or better @ 5000 RPM then the stator is in good shape. The internal construction on the aftermarket rectifier/regulators is different than the stock Suzuki stuff so the test ohms could be entirely different.

Also, check that you have good grounds for the R/R and the battery. That has been a deal breaker on many GS Suzukis.

Hap

[hotdergs07]

I was able to borrow an amp clamp for this upcoming weekend to do some more testing to verify wether or not the is an excess load on the charging system somewhere else. If that is unsuccessful I'm going to take apart the generator cover and see how everything looks in there, I will probably replace the connectors as well. They don't look very clean as it is. I'll keep you posted after I do the repairs this weekend.

[Hap Call]

I was able to borrow an amp clamp for this upcoming weekend to do some more testing to verify wether or not the is an excess load on the charging system somewhere else. If that is unsuccessful I'm going to take apart the generator cover and see how everything looks in there, I will probably replace the connectors as well. They don't look very clean as it is. I'll keep you posted after I do the repairs this weekend.

Make sure it is a DC amp clamp meter, not an AC.

Hap

[Steve]

Actually, if you are using the amp clamp on the stator wires, don't you want AC? :-|

Yes, you do want a DC clamp if you put it on anything downstream of the regulator, like the battery wire. 8-[


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[hotdergs07]

i thought amps were amps and it didn't matter wether it was AC or DC??? Ive think i have tested amperage on charging wires on a car with this clamp before...