Voltage Regulator or Stator?

[rcuppernall]

My 2008 xb12 is not holding a battery charge. I have already checked the battery and used another just to make sure and they both are drained when im done riding.

Here are the symptoms.
-shutting off when coming to or stoped
-battery drained after riding it for no longer the 15 min
-all of my lights are NOT dimming when i use the throttle.
-it coughs and sputters when i am stopped.
-check engine light is on. tested and is code 16

I have narrowed it down to either the Voltage Regulator or the Stator. i need some help because i do not want to put out the money to have it diagnosed.


Can i test these with a volt meter and is there a diagram or example somwhere to show me how?

 

[raz65man]

Start here:
Test thread
Excellent write-up on stator replacement here:
Stator replacement
A manual will really help the process. Plus both threads cover older model of bike. 08-09 models the plug/connectors going from stator to VR, and VR to battery are up under the left frame behind the left side scoop.
When I had an issue I did not trouble shoot far enough and just replaced the VR first time. Second time around I found that the stator was pumping 55+ volts into the VR and frying it.
Hope this helps,
Raz

 

[rcuppernall]

k that helps me with installing things but i really need help with figuring out what is wrong with the damn thing

 

[c818919]

Voltage reg....

 

[raz65man]

There are a couple of links within the test thread that may help also. Basicly if checking at the battery, you should be getting 14 volts at idle,14.3-14.5 at roughly 2000 rpm. If not, find the wire harness coming from the stator, exits from behind the primary just below the starter and comes up under the left side frame where it has a plug that connects to the VR.(08-09) On the plug coming from the stator you should get 20 volts ac at idle and 28 at 2000 rpm. Going by memory here so I may be off a little.
There is another plug there also,. That is the one coming back from the VR to the battery. Try to find a manual, it will help tremendously.
Raz

 

[FIDOSOL]

The manuals are linked at the top of the page.

 

[Macbuell]

assume volt reg. Stators fail less frequently. This has also happened to my bike. Was not the easiest thing to fix though. Putting and wiring up the new plug was a pita

 

[rcuppernall]

Ok yeah so going through the service manual slowly i am pretty sure it is the Voltage Regulator. Going to do tests this weekend when i get a volt meter which will be today. thanks for reminding me about the manuals FIDOSOL.

 

[FIDOSOL]

I do what I can, I don't want you to go through as much heartache as I did.

On my 4th battery.
On my 2nd voltage regulator.

Just pay it forward man.

 

[BitchinXb]

Have you been blowing fuses and headlights?

 

[rcuppernall]

Have you been blowing fuses and headlights?

No nothing like that. just the battery is draining on me while i ride.

this voltage metere is so confusing to understand. i have no idea which one to click it on...lol[confused]

 

[rcuppernall]

Ok so I checked te voltage on the battery it was 12.7
When I turned it on it read 13.0-13.2
When reved to 3000 it was 14.0-14.2

That seems like it checks out! No regulator?

 

[XbWolf]

Have you been blowing fuses and headlights?

i'm blowing headlights like crazy man!?!???!!

AINT NOBODY GOT TIME FA DAT!


is this a voltage regulator problem?

 

[BKKBuell]

What do u mean: bat drained after 15min? means ur bat is empty after 15min?
If this is the case u have a wire short to ground or leaking/bad connection which would explain as well the shuting down... Do u know how to check?

 

[Macbuell]

Ok so I checked te voltage on the battery it was 12.7
When I turned it on it read 13.0-13.2
When reved to 3000 it was 14.0-14.2

That seems like it checks out! No regulator?

Not a single one of those numbers indicate any sort of battery OR regulator problem....

You narrowing it down to battery or volt reg are wrong.

-all of my lights are NOT dimming when i use the throttle. - not volt reg.

-battery drained after riding it for no longer the 15 min - what makes you think this if your numbers above are correct?

 

[Macbuell]

Sorry for the misinformation I provided before, but given this new information you were wrong when you "narrowed it down to the battery or volt reg". You have another problem...

Without a working volt reg your lights would have dimmed when revving, and you never would have made it to 14 volts.

 

[Ebeo1]

I found this thread when doing research for my problems so I throw up my information might help some one else later on. I have a 2009 XB12R the headlights would dim when I was driving through town and I thought it was a bulb going bad. Eventually my battery died and after buying a new one and getting stranded I new I had bigger issues.

First I checked the battery to see where the level was I didn't know what to expect when the bike was running for charging voltage but I was betting it would charge at 13v DC or more. This picture was taken right before pushing the start button so key was on, low beams, tail light, and license plate lights were all on.

Then I started the bike to see if it was charging or not so anything greater than what I started with would have been nice. Instead it was actually lower meaning I had added another load to the system (spark plugs) and it was not charging.

This led me to the fact the charging system was not working two of the major culprits are the voltage regulator or the stator. The connections for both are located behind the air scope so I removed it. The round gray connection comes from the stator plugs into a black connection to the V.R. so it will read a AC voltage at that connection. The other connection a rectangular two plug connection comes from the V.R. and feeds the motorcycles DC system so it will read a DC voltage.

Unplugging the gray connection and testing it for AC voltage shows that it was making 28 volts when the motorcycle was at idle.

Revving up the engine would cause the voltage to increase so checking it again found it to be a higher voltage at about 60. The voltage was also noticed to be anywhere between 51 to 73 volts AC but was most consistent around 60.

I was concerned this was too high of a voltage and with out the buell electric diagnostic manual wouldn't know if I was putting out too much voltage. I called Al at American sport bike and he reassured me the voltage was suppose to be about that high so I ordered a new voltage regulator which is about $130. Hopefully this will get me back on the road.

 

[TPEHAK]

Have you fixed the problem? Did you check the voltage regulator output?

It looks like my 2009 Buell XB 12Scg has battery charging issue. Yesterday I was not able to start my motorcycle after one hour trip and battery voltage dropped to 11.8 volts, but before the trip it was fully charged. I checked the stator according 2008 Buell XB Electrical Diagnostic Manual manual and it is OK (0-0.1 ohms resistance between the plug 46 pins, there is no continuity between the plug 46 pins and motorcycle ground, the plug from the stator has 30 volts AC at 1200 RPM, 50 volts AC at 2000 RPM, 72 volts AC at 3000 RPM).

Then I connected the the stator to the voltage regulator and disconnected the voltage regulator from the plug 77. Then I started the motorcycle and measured DC voltage from the plug 77 from the voltage regulator side, and it shows 1.8 volts DC at any RPM. Does this mean that the voltage regulator is bad? The wires on the voltage regulator between the plug 46 and the plug 77 looks OK. The plug 46 look OK. The plug 77 look OK too.

When I connected all together and measured the DC voltage on the battery terminals it showed 12.9 volts DC at 1200 RPM, 14.25 volts DC at 2000 RPM, 14.27 volts DC at 3000 RPM, 14.28 volts DC at 3600 RPM.

 

[Cooter]

After 4 years I hope so! Haha.
11.8 volts is low (and could be a problem) but a no start? would it just not crank? just click? crank slow and not start?
Before the trip it was fully charged? how do you know?
How did you check the Stator exactly? did you OHM out each lead? or check the output while running?
I'm not sure what unplugging the '77' connector while running does. The way I understand it, the VR needs to be connected to the Stator AND the battery to operate.

All that aside, the simplest check for you to do is with the same voltmeter.

Attach it to the battery. Whats the voltage? (should be 12+ volts)
Crank it. How low does the voltage go? (should be more than 9.6 volts)
What is the Voltage at idle? (should be more than resting voltage)
What is the Voltage at 2500RPM? (should be 12.5-14.7 volts)

That will tell you if you need a battery, or if the charging system needs repair.

 

[TPEHAK]

Thanks for your help!

Yes it was fully charged. And I always know voltage on the battery when I park the motorcycle because I have Scorpio alarm system with telemetry. Here is the story. The motorcycle battery was on the charger before the trip (I always keep the battery on the charger because the motorcycle has extra accessories like Scorpio alarm system, m-lock and sometimes I use First Gear heated gear for cold days (but that day I did not turn on the heated gear), plus I use motogadget mini cluster with a bunch of relays instead of standard cluster, so they eat some amperes. I performed Milliampere Draw Test on parked motorcycle with attached m-lock and activated alarm system and it eats up to 10-18 milliamperes from the battery when motorcycle is resting. If I isolate the m-lock and the alarm system it eats 1.1 milliamperes with no accessories on the parked motorcycle. Does this mean a shortened wire in the accessories circuit or is it normal?

By the way, I washed my motorcycle with water before the trip, so maybe it can be a part of the reason? I've modified the tail section with tail light and the headlight is modified too so there can be some open wires and water can shorten them. I know that my new wiring has some water resistance issues, because if I ride under the rain my oil pressure check LED light can turn on and off for short time in half brightness like there is a connection between the oil pressure check wire and the motorcycle ground.

Yesterday after one hour trip I parked the motorcycle and according the Scorpio alarm telemetry the battery had 11.8 volts. Then I tried to start the motorcycle, but at 11.8 volts my m-lock relay just disconnecting the power from the battery while the starter was trying to crank the engine, so I shortened the m-lock relay contacts to eliminate the problem, but the motorcycle starter was not able to crank the engine and it was just clicking. So I roll the motorcycle to the gas station and asked a car driver to connect his car battery and started my bike. Then I rode 1 hour back to home and at home the battery showed 12 volts and I was able to start the bike with no jumping! Sounds like it was charging on the back way.

Today I tested the charging system. Before the test I fully charged the battery.

The 2009 Buell XB stator has 2 wires. I disconnected the plug 46 from the stator (under the left air scoop) and measured resistance between the plug 46 pins on the stator side, it showed 0 (zero) to 0.1 Ohm. Then I measured the resistance between the both plug 46 pins from the stator and the motorcycle ground and it was infinite (no continuity). I performed all these measurements with no motorcycle starting. Then I started the motorcycle with disconnected stator and measured the AC voltage on the the plug 46 from the stator, it showed 30 volts AC at idle 1200 RPM, 50 volts AC at 2000 RPM, 72 volts AC at 3000 RPM. So the stator is fine.

Next, I connected the stator back to the voltage regulator and disconnected the voltage regulator from the plug 77 under the right side air scoop. I connected the voltmeter to the plug 77 from the voltage regulator side and started the motorcycle. The voltmeter showed 1.8 volts DC at any RPM. I'm not sure this is the right way to test the voltage regulator.

Then I connected all this stuff back to initial condition (the stator connected to the voltage regulator and the voltage regulator connected to the motorcycle circuit), started the motorcycle engine and measured DC voltage on the battery terminals. It showed 12.9 volts DC at idle 1200 RPM (it is more than 12.7-12.6 volts while resting with no lights and the key switch is turned off, and it is more than 12.1-12.2 volts while resting with lights and the key switch is turned on), 14.25 volts DC at 2000 RPM, 14.27 volts DC at 3000 RPM, 14.28 volts DC at 3600 RPM.

When the battery is fully charged the voltmeter shows 12.7 volts DC on the battery with lights turned off at resting. When I turn on the key and the lights the DC voltage on the battery drops to 12.2 volts. When I start the fuel pump the DC voltage on the battery drops to 12.1 volts while fuel pump is pumping. When I crank the starter the voltage on the battery can drop below 7 volts for very short time if it is struggling with crank, or it can drops just to 10 volts for very short time if it is easy to crank, it is always different.

I inspected the wires and the plugs under the left side scoop and they are in good condition.
I use motogadget mini cluster and relays for the cluster lights, and LED turn signal flasher, they might eat some extra amperes comparing with the original equipment, or there can be a shortened wire in my new wiring? Should I perform Milliampere Draw Test? The bad thing is my digital voltmeter are not capable to perform this test with high amperes.

Is it bad battery? I bought the most expensive Duracell AGM battery just a year ago and I always keep the battery on the charger.

The weird thing is that it never happened before yesterday. It was like I rode the motorcycle with disconnected stator or with extra load on the battery like shortened wire. I believe even the battery is bad the charging system should keep the battery above the low voltage. Now I just can not trust the motorcycle to take it more than 1 hour away from home.

Maybe I will go to the the auto parts store next to me and ask them to perform the battery load test.