Charging System Troubleshooting
 

Hi,

Battery ran dead yesterday. Jumped bike, got home, took battery out, and put on my consumer grade charger at 2A until it reported full.

Performed the troubleshooting steps in service manual this morning, here are my results:

Battery Voltage:
- With key off or battery out of bike: over 12.3V but under 13V - I think it was 12.8 or so.

Current Leakage Test:
- Leakage of about .5 mA
- Pulled the ODO Fuse, Current Leakage dropped to zero
(in the "Odometer Frozen" thread, I seem to have concluded that I need a new speed sensor, for what that is worth)

Question: the original poster of that Odometer Frozen thread also reported that he was seeing excessive leakage here, and pulled his fuse. Is this a common problem - does this suggest that something's wrong with my instrument cluster - will the speed sensor swap magically resolve this?

Regulated Voltage Inspection Test:
- Previous owner changed R/R a couple years ago to the newer model with the heat sink
- Regulated Voltage is under 13.5V at 5k RPM

Regulator/Rectifier Test
- Battery Line - shows battery voltage - ok
- Ground line - shows continuity - ok
- Charging Coil Line resistance - all combinations showed approx 1 ohm - out of spec
- Continuity Check between yellow wires and ground - no continuity - ok

Alternator Charging Coil Test:
- (I'm assuming that I am checking the right 3-prong connector here - the only other connector with 3 pins is the one for the speed sensor)
- Charging Coil Line resistance - all combinations showed approx 1 ohm - out of spec
- Continuity Check between all wires and ground - no continuity - ok






Ok - so I want to make sure that I am interpreting these things correctly.

From the flow diagram in the service manual, I believe the results above indicate a good R/R but a faulty Alternator Charging Coil. Is this Correct?

--> if so, does anyone have the part number for the stator and crankcase cover gasket?
--> should I let a shop do this, or should I use this as an excuse to buy a torque wrench? It doesn't seem that difficult but I don't want to screw anything up.

Does it sound like I need a new battery as well?

Anything else I am overlooking from the results posted above?

Really appreciate it guys,

Justin

Do the battery first, the other problems may go away. One ohm off spec on the stator may be the accuracy of your meter, not a bad coil.

Ohm checks are OK but not as good as a dynamic check. I agree with thetophatflash that the ohms being one out is not an issue. If you really wanted to check them start the bike and check for AC voltage at the stator wires. Unplug the connector with the three yellow wires coming from the stator. Check each one to the other as you rev the bike it should go up to something like 80 or 100 volts. It should be way up there. The book may give an actual spec. particularly if one leg is lower than the others then it's probably bad. But from what you're describing I'm guessing it's fine.

Did you do the rectifier diode check where you check for continuity between the 3 yellow wires to the red then to the black wire on the RR? Going one way for example red meter lead to yellow and black meter lead to black should give a resistance reading and then reversing black meter lead to yellow and red meter lead to black should have no resistance or continuity. Check both ways from the yellow wires to the black wire as well as from the yellow wires to the red wire. This is checking all the diodes in the rectifier to make sure it's good.

If anything it sounds like the regulator isn't putting out full voltage if it's not more than 13.5. It should usually go at least 13.5 up to low 14 range depending on the regulator.

Since your speed sensor seems to be pulling 5 volts continuously, I would look into this. Repeat the current leakage test with everything connected EXCEPT the speed sensor. If the leak is now below .1 mA then plug the speed sensor in and see if it jumps back up to .5 mA. If the leakage is present with the sensor unplugged then unplug the 3p stator connector (charging coil) followed by the regulator plug. If leakage is still present then something is wrong in the dash cluster.

I did this test. the leakage only showed .3-.4 A this time (still too high but slightly lower than the .5A as seen this morning) but it still shows this leakage with speed sensor, regulator, and charging coil disconnected. the leakage disappears when I pull the ODO fuse.

do I need to replace both the instrument cluster as well as the speed sensor??

now on to perform the other tests recommended this afternoon.

I tried the above and I'm confused. regardless of which combination of probe color, I saw absolutely nothing for resistance between any of the yellow wires and either the red or black wire?

Do you know what the battery voltage was prior to charging? Did you check max voltage at the battery at, say 2500 rpm?

I don't recall but it was in the high 10.x range I believe.

the voltage at battery did increase slowly with rpm but didn't reach 13.5 even at 5k rpm.

if it matters, I had started the bike at least 20 times in the 24 hour period prior to it dying. my guess is that something happened with the charging system either late last season or over the winter, and the limited times the bike has been driven this year, the battery itself has simply held up.

I have battery on recondition cycle on charger at the moment. it is a 3-4 year old yuaza.

I believe that you may have one or two cells that are failing. Fully charged should be in excess of 13.5 vdc. Load test it by turning the key on and check the voltage at the battery. I believe you'll see it drop below 11 vdc almost instantly.

Thanks for the advice.

I'll check how the battery recondition cycle goes and replace if I can't get above 13V.

It seems that even if I have a faulty battery, I still have a charging problem - by the fact that the voltage did not rise properly at 5k rpm? Based on the data in this thread, are you guys thinking that it would be the R/R or the alternator charging coil?

Also - BeerHunter, should I spend money on the speed sensor or is it possible that by instrument cluster is fubar?

Take care,

Justin

I have repeated the current leakage test on my own bike. Meter shows 0.56 mA. The book says anything over 0.1 mA is a problem. I have no battery or charging problems. I suspect the book is in error. It likely should read 1.0 mA or over = problem.

Speed sensor. When testing, did you measure volts between + pink/green and - green/black with the connector attached to the sensor? (the sensor must be connected to the harness) You need to probe the wire in the back of the connector. It only takes a small wheel movement to produce a voltage change. Move the wheel a little, 4.7 volts and stop turning. The reading should stay the same. Move it a little more, it should change to 0, stop turning and you not have 4.7 steady. Repeat.

If you did this and have a constant 5 volt reading while turning the wheel S L O W L Y then the sensor is stuck closed and needs to be replaced.

Your gauges seem to be fine.

When testing the diodes in a regulator, you need a meter that has a Diode Test function.
http://www.divms.uiowa.edu/~jones/vo...iode/diode.gif

When GTS refers to resistance readings, that will appear on the meter as Volts DC.


ElectroSport has a couple PDF files that may be useful.

The first explains how to test their own products. It can be used for other regulators too, but the number values may be different. What is more important are any differences among the 3 legs of the system.

ElectroSport Regulator testing


This one is also helpful for general motorcycle charging system diagnostics.


ElectroSport charging system diagnosis


Is there any discoloration of the wiring at and near the connectors for the stator and regulator? Or have the wires become hard? Are the connectors showing any signs of corrosion?

Thanks BeerHunter, I will check those links out.

To answer your question, no discoloration on the wires and they seem fairly healthy.

I may not have been using the proper setting on my multimeter for those tests.

Sorry I didn't clarify to use the diode check function on your multi meter. Most meters will have this. Some of the really cheap ones don't though. I'm guessing your RR is bad from what I'm hearing so far. It's possible it's a battery though. A bad battery can cause all sorts of wierd issues with charging and other systems.