Bad battery, or rectifier/regulator ???

[Rusty McNeil]

As stated below,if you not seeing full voltage at the battery it could be many different causes, the best way to test this is to check the voltage directly at the R/R, both for AC in (the stator output) and at the closest connector to the R\R for DC out, if your regulator doesn't have a ground wire use the metal body of the R/R for your negative lead. This will tell you truly what the R/r is doing and disregard any other connection issues.

Once you do that leave the negative lead on the R/R and move the positive to the battery terminal, and vice versa by putting the positive lead on the R/R positve wire and the negative lead on the battery, this will tell you whether you have a poor ground path to the battery via the R/R to frame connection, throught the frame and the battery to frame jumper wire, or a bad positive path throught the wiring harness, or both.

You can also check for voltage drop directly across the connectors across the SAME wire, looking for poor spade lug connections inside the connector, when doing this you are not looking for full battery voltage but instead looking for a drop due to current moving across a high resistance, poor connection, (it helps to have the headlights on, maybe the fan to if you have a switch for it, since the extra load will increase the voltage drop and make it easier to find) the voltage measured should be very close to ZERO, if it's not zero then that is voltage that's being dropped across high resistance connections and not being put across the battery.

Whatever you get directly off the R/R should be making it to the battery.

If your R/R doesn't have a negative wire, or has a negative wire that only goes to the frame of the bike, I would recommend running a wire directly from the mounting point of the R/R to the battery in the first case, or from the negative wire to frame point directly to the battery in the second case. You want to get away from using the frame or engine case for negative/voltage current path. This solved all my problems and I am now seeing 14+ volts 1500 rpm or better and 13.4volts at idle.

You can also run a separate ground wire directly from the starter to the battery and ensure your starting current ground path does not rely on the engine case, although this mod will do nothing for your charging system, it only affects the ability of the starter to recieve full voltage when starting.

The connector from the R/R to the battery......., the 12volt side......, I shit canned the connector and ended up butt spliceng and soldering to get rid of the shitty spade connectors in the connector, and also did the same thing for the three white wires carrying AC to thr R/R.

My belief is that most mechanics don't have a clue when it comes to using a meter to diagnose where the voltage drops are occuring in an electrical circuit, hell, most electricians I know don't either, they monkey see monkey do this stuff without understanding why. You can probably better troubleshoot it yourself with a little help from guys on this forum and save yourself a load of money in the process.

"pull it, land it, don't understand it" is their motto........

Charging issues on the Max are rarely from component failure but more likely to be poor connections and harness issues. The wiring harness is very poorly designed and relies way to much on the frame and engine for current/voltage paths, but is easily remedied...only after doing that would I be willing to pronounce a component failure.......

An oddysey battery is considered fully charged when at 12.84volts @ 68 degrees F and a stock vmax R/R that doesn't have any wiring problems is more than up to the task of charging one of these. Rapid chargers need between 14.2 volts and 15 volts and float constant chargers around 13.2 to 13.8 volts. If you insist on keeping a "trickle" charger on an AGM battery (they are NOT gel, I don't care what anyone says, gel are almost non-existent these days) then I would recommend a "smart" charger designed for the application, a "dumb" charger will not regulate the voltage and current properly and can (not will) undercharge or overcharge your battery and ruin it.

I wouldn't run any separate charger on one of these if it were me, if the charging system is operating properly and putting at least 13 volts or so to the battery, simply start the dang thing and let it warm up once a week and you'll be doing your carbs a favor too....

"

 

[Miles Long]

quote....

"You can also check voltage directly across the connectors, the voltage measured should be very close to ZERO, if it's not zero, then that is voltage that's being dropped across high resistance connections and not being put across the battery.

Whatever you get directly off the R/R should be making it to the battery.

If your R/R doesn't have a negative wire, or has a negative wire that only goes to the frame of the bike, I would recommend running a wire directly from the mounting point of the R/R to the battery in the first case, or from the negative wire to frame point directly to the battery in the second case. You want to get away from using the frame or engine case for negative/voltage current path. This solved all my problems and I am now seeing 14+ volts 1500 rpm or better and 13.4volts at idle.
Charging issues on the Max are rarely from component failure but more likely to be poor connections and harness issues. The wiring harness is very poorly designed and relies way to much on the frame and engine for current/voltage paths, but is easily remedied...only after doing that would I be willing to pronounce a component failure......."


Hey Rusty -
Miles Long here, the originator of this thread, way back in August......
I originally had two questions, the first one(battery voltage) being resolved (see post #14)
Your reply above seems to answer my second concern, that is, whether it is possible to test the output of the RR itself. A quote from my original post...
"The Clymer manual says there is no way to test an RR, but also states that the "voltage regulator no-load output" should be 14-15 volts.
My questions-
#1 - Even with a bad or partially discharged battery, if the charging system is working properly, will a running bike show 14+ volts across the battery terminals?? Answer... NO!
#2 - Why can't the output of the RR be checked, even though the manual says there is no way to test? I pulled apart the separate black and red RR connections (the ones next to the 3 wire stator connector) and checked the DC voltage. It only showed about one volt at the red wire, at 4000 rpm. Has anyone else every measured this voltage? Should it be the full 14-15 volts, or does that figure only apply to voltage across the battery terminals?" Answer...14-15 volts applies to battery terminal voltage

So you see, when I measured the voltage across the RR, I got very little.
Your answer seems to indicate this is normal for a healthy unit, and that the small amount measured is resistance caused by bad connections. I eventually will do as you (and so many others) have done, that is, cutting out the connectors and soldering, and providing a better ground for the RR. This will hopefully reduce the voltage to "very close to zero"
And I agree with you, even though my electrical problems have been minimal, most of these can be traced back loose or poor connections, not component failures.
Hopefully, people that are having charging problems will read your answer, and realize that there is a way to test the RR electrically, contrary to what the manuals might say. Might save them some grief, maybe reduce the troubleshooting process, and save money, by not replacing perfectly good components.
Thanks for the answer Miles











?

 

[Rusty McNeil]

quote....

"You can also check voltage directly across the connectors, the voltage measured should be very close to ZERO, if it's not zero, then that is voltage that's being dropped across high resistance connections and not being put across the battery.

Whatever you get directly off the R/R should be making it to the battery.

If your R/R doesn't have a negative wire, or has a negative wire that only goes to the frame of the bike, I would recommend running a wire directly from the mounting point of the R/R to the battery in the first case, or from the negative wire to frame point directly to the battery in the second case. You want to get away from using the frame or engine case for negative/voltage current path. This solved all my problems and I am now seeing 14+ volts 1500 rpm or better and 13.4volts at idle.
Charging issues on the Max are rarely from component failure but more likely to be poor connections and harness issues. The wiring harness is very poorly designed and relies way to much on the frame and engine for current/voltage paths, but is easily remedied...only after doing that would I be willing to pronounce a component failure......."


Hey Rusty -
Miles Long here, the originator of this thread, way back in August......
I originally had two questions, the first one(battery voltage) being resolved (see post #14)
Your reply above seems to answer my second concern, that is, whether it is possible to test the output of the RR itself. A quote from my original post...
"The Clymer manual says there is no way to test an RR, but also states that the "voltage regulator no-load output" should be 14-15 volts.
My questions-
#1 - Even with a bad or partially discharged battery, if the charging system is working properly, will a running bike show 14+ volts across the battery terminals?? Answer... NO!
#2 - Why can't the output of the RR be checked, even though the manual says there is no way to test? I pulled apart the separate black and red RR connections (the ones next to the 3 wire stator connector) and checked the DC voltage. It only showed about one volt at the red wire, at 4000 rpm. Has anyone else every measured this voltage? Should it be the full 14-15 volts, or does that figure only apply to voltage across the battery terminals?" Answer...14-15 volts applies to battery terminal voltage

So you see, when I measured the voltage across the RR, I got very little.
Your answer seems to indicate this is normal for a healthy unit, and that the small amount measured is resistance caused by bad connections. I eventually will do as you (and so many others) have done, that is, cutting out the connectors and soldering, and providing a better ground for the RR. This will hopefully reduce the voltage to "very close to zero"
And I agree with you, even though my electrical problems have been minimal, most of these can be traced back loose or poor connections, not component failures.
Hopefully, people that are having charging problems will read your answer, and realize that there is a way to test the RR electrically, contrary to what the manuals might say. Might save them some grief, maybe reduce the troubleshooting process, and save money, by not replacing perfectly good components.
Thanks for the answer Miles








?

I think maybe when they say there is no way to check the R/R they mean to check it for individually burnt out diodes??? Not sure about that (although there is a way to check for this by checking the AC output of the R/R if diodes are starting to go bad, then the AC "ripple" is going to go up, a perfect rectifier will not have any AC, but these aren't perfect even when new since they don't have the filtering to remove all the AC ripple, but you would have to know your baseline when new for the number to tell you anything since all DC systems make a small amount of AC unless they have a really good power supply type filtering capacitor etc), ..............The R/R voltage is what goes to the battery so checking the R/R at the nearest connector on the side of the connector nearest the R/R should be the R/R VOLTAGE check, the ground reference is a little iffy since some don't have the ground wire and you have to use the metal case of the R/R as your ground reference....

My method simply eliminates the wiring between the R/R and the battery and tells you what the R/R itself is putting out.


By checking voltage across the connector and looking for zero I mean to say across both sides of the same wire, checking the voltage drop across the spade lugs inside the connector itself, it helps to have the headlights on when doing this since the load is going to make the voltage drop greater and easier to find, if there is no load then there will be no voltage drop......if you check it from the red wire to the case of the R/R or the negative ground wire if there is one then you should read full voltage since this is what is going to the battery.

When you got little or nothing at the connector what were you using as your negative or ground reference?


I've never troubleshot a system with a bad battery in place, but since watts (which is a fixed capacity for a charging system) equals amps * volts then if the amps are higher due to trying to charge a bad battery then the volts are going to be accordingly lower....simple ohms law....

Another trick is to install a headlight kill switch and turn the headlights off when the bike is going to be idling for very long, this will help to ensure your bike is charging instead of draining when at idle..

I just went outside and checked mine and the battery was at 12.7 after not being started for 3 weeks (working out of town) and when I started it it jumped to 13.9 and then climbed to 14.3 at 1300 rpm...with the headlight off. At 900 rpm idle it makes 14.2...when I turn the headlight on (modified cybermax...2 ea. 100 watt lamps) it drops to 13.7 volts at 900 rpm idle......The battery is a 3 year old Oddyssey...

I also forgot to turn the fan on and overheated it (it hit the overflow) while I was in here typing so maybe I'm not so smart after all huh? lol!

 

[Miles Long]

I think maybe when they say there is no way to check the R/R they mean to check it for individually burnt out diodes??? Not sure about that (although there is a way to check for this by checking the AC output of the R/R if diodes are starting to go bad, then the AC "ripple" is going to go up, a perfect rectifier will not have any AC, but these aren't perfect even when new since they don't have the filtering to remove all the AC ripple, but you would have to know your baseline when new for the number to tell you anything since all DC systems make a small amount of AC unless they have a really good power supply type filtering capacitor etc), ..............The R/R voltage is what goes to the battery so checking the R/R at the nearest connector on the side of the connector nearest the R/R should be the R/R VOLTAGE check, the ground reference is a little iffy since some don't have the ground wire and you have to use the metal case of the R/R as your ground reference....

My method simply eliminates the wiring between the R/R and the battery and tells you what the R/R itself is putting out.


By checking voltage across the connector and looking for zero I mean to say across both sides of the same wire, checking the voltage drop across the spade lugs inside the connector itself, it helps to have the headlights on when doing this since the load is going to make the voltage drop greater and easier to find, if there is no load then there will be no voltage drop......if you check it from the red wire to the case of the R/R or the negative ground wire if there is one then you should read full voltage since this is what is going to the battery.

When you got little or nothing at the connector what were you using as your negative or ground reference?


I've never troubleshot a system with a bad battery in place, but since watts (which is a fixed capacity for a charging system) equals amps * volts then if the amps are higher due to trying to charge a bad battery then the volts are going to be accordingly lower....simple ohms law....

Another trick is to install a headlight kill switch and turn the headlights off when the bike is going to be idling for very long, this will help to ensure your bike is charging instead of draining when at idle..

I just went outside and checked mine and the battery was at 12.7 after not being started for 3 weeks (working out of town) and when I started it it jumped to 13.9 and then climbed to 14.3 at 1300 rpm...with the headlight off. At 900 rpm idle it makes 14.2...when I turn the headlight on (modified cybermax...2 ea. 100 watt lamps) it drops to 13.7 volts at 900 rpm idle......The battery is a 3 year old Oddyssey...

I also forgot to turn the fan on and overheated it (it hit the overflow) while I was in here typing so maybe I'm not so smart after all huh? lol![/QUOTE

Thanks for the detailed reply, Rusty. I checked your public profile to find out your occupation. This forum needs more troubleshooting electrical technicians like yourself, based on the number of electrical inquiries. Expecting yourself to answer them all is too much of a burden, I suspect?
During my career I worked with many excellent electricians, but not all of them had the ability to perform detailed troubleshooting. It's a gift.
When I checked my RR for DC output, I used the black groundwire connector for earth. I thought I was going to get 14-15 volts, as you say would be normal for a properly working unit. As I said previously, I measured less than one volt. I'm going to have to check that one again.I'm thinking now I may have have the negative lead on the RR black spade, not it's mating unit that goes into the wiring harness. Stupid me!
Using Ohm's law to explain the charging battery terminal voltage....with a partially discharged battery.....takes the mystery out of the low readings.
There are SO MANY posts from folks concerned about their charging voltage . How many check their batteries for full charge before condeming wiring, connectors and components?
I installed a headlight override switch years ago, not for prolonged idling reasons, but because I use two 371/2 volt halogen sealed beams as my only light source up front, during daylight hours. The beams (G.E.H7616)are "spot" lights( the glass lens has no fluting at all), and are extremely bright. I turn these off when starting the bike. The front running lights in the turn signals have been disabled as well, and are now on a switched "running lights" circuit, that includes 6 other LED marker lights.
I also replaced the stock headlight with a 7" automotive conversion headlight . I have never been too happy with the stock 60/55 bulb, however, and would like to try a higher wattage unit , maybe a 90/70, if they make such an animal, and the charging system will handle it(plus the spot lights). How long have you been using the cybermax arrangement? Are both bulbs on at the same time?(200 watts?!) Are you running a stock stator?
"I also forgot to turn the fan on and overheated it"
What kind of arrangement do you have for your cooling fan? Did you cheat around the thermoswitch completely? If so, why?
Cheers, Miles
p.s. Also checked out your Yellowstone album. I was out that way in '08, luved it! Great riding territory, eh???

 

[Rusty McNeil]

I think maybe when they say there is no way to check the R/R they mean to check it for individually burnt out diodes??? Not sure about that (although there is a way to check for this by checking the AC output of the R/R if diodes are starting to go bad, then the AC "ripple" is going to go up, a perfect rectifier will not have any AC, but these aren't perfect even when new since they don't have the filtering to remove all the AC ripple, but you would have to know your baseline when new for the number to tell you anything since all DC systems make a small amount of AC unless they have a really good power supply type filtering capacitor etc), ..............The R/R voltage is what goes to the battery so checking the R/R at the nearest connector on the side of the connector nearest the R/R should be the R/R VOLTAGE check, the ground reference is a little iffy since some don't have the ground wire and you have to use the metal case of the R/R as your ground reference....

My method simply eliminates the wiring between the R/R and the battery and tells you what the R/R itself is putting out.


By checking voltage across the connector and looking for zero I mean to say across both sides of the same wire, checking the voltage drop across the spade lugs inside the connector itself, it helps to have the headlights on when doing this since the load is going to make the voltage drop greater and easier to find, if there is no load then there will be no voltage drop......if you check it from the red wire to the case of the R/R or the negative ground wire if there is one then you should read full voltage since this is what is going to the battery.

When you got little or nothing at the connector what were you using as your negative or ground reference?


I've never troubleshot a system with a bad battery in place, but since watts (which is a fixed capacity for a charging system) equals amps * volts then if the amps are higher due to trying to charge a bad battery then the volts are going to be accordingly lower....simple ohms law....

Another trick is to install a headlight kill switch and turn the headlights off when the bike is going to be idling for very long, this will help to ensure your bike is charging instead of draining when at idle..

I just went outside and checked mine and the battery was at 12.7 after not being started for 3 weeks (working out of town) and when I started it it jumped to 13.9 and then climbed to 14.3 at 1300 rpm...with the headlight off. At 900 rpm idle it makes 14.2...when I turn the headlight on (modified cybermax...2 ea. 100 watt lamps) it drops to 13.7 volts at 900 rpm idle......The battery is a 3 year old Oddyssey...

I also forgot to turn the fan on and overheated it (it hit the overflow) while I was in here typing so maybe I'm not so smart after all huh? lol![/QUOTE

Thanks for the detailed reply, Rusty. I checked your public profile to find out your occupation. This forum needs more troubleshooting electrical technicians like yourself, based on the number of electrical inquiries. Expecting yourself to answer them all is too much of a burden, I suspect?
During my career I worked with many excellent electricians, but not all of them had the ability to perform detailed troubleshooting. It's a gift.
When I checked my RR for DC output, I used the black groundwire connector for earth. I thought I was going to get 14-15 volts, as you say would be normal for a properly working unit. As I said previously, I measured less than one volt. I'm going to have to check that one again.I'm thinking now I may have have the negative lead on the RR black spade, not it's mating unit that goes into the wiring harness. Stupid me!
Using Ohm's law to explain the charging battery terminal voltage....with a partially discharged battery.....takes the mystery out of the low readings.
There are SO MANY posts from folks concerned about their charging voltage . How many check their batteries for full charge before condeming wiring, connectors and components?
I installed a headlight override switch years ago, not for prolonged idling reasons, but because I use two 371/2 volt halogen sealed beams as my only light source up front, during daylight hours. The beams (G.E.H7616)are "spot" lights( the glass lens has no fluting at all), and are extremely bright. I turn these off when starting the bike. The front running lights in the turn signals have been disabled as well, and are now on a switched "running lights" circuit, that includes 6 other LED marker lights.
I also replaced the stock headlight with a 7" automotive conversion headlight . I have never been too happy with the stock 60/55 bulb, however, and would like to try a higher wattage unit , maybe a 90/70, if they make such an animal, and the charging system will handle it(plus the spot lights). How long have you been using the cybermax arrangement? Are both bulbs on at the same time?(200 watts?!) Are you running a stock stator?
"I also forgot to turn the fan on and overheated it"
What kind of arrangement do you have for your cooling fan? Did you cheat around the thermoswitch completely? If so, why?
Cheers, Miles
p.s. Also checked out your Yellowstone album. I was out that way in '08, luved it! Great riding territory, eh???

The Cybermax lamps are both on at the same time, although I installed a switch to allow only one so it would pass inspection for hi-lo beam operation. The stock Cybermax bulbs are lower wattage, I installed the higher ones myself and got rid of the crappy diode they send you for high-low beam switching.

Everything else on the bike is converted to LED so I guess the stator isn't overloaded with the 2-100 watt bulbs on, it's been running this way for 20,000 miles with n o ill effects. I can't remember what the wattage is rated on the vmax stator but I do remember that beside the headlight the biggest next load is the TCI which I think pulls maybe 40-60 watts, after that its very small bulb loads and the intermittent fan.


The Cybermax headlight light output leaves a LOT to be desired, and even with the 2 100 watters in there it is just barely as good as stock, but I avoid night riding like the plague anyway so it's not much of an issue to me......The visibilty of the headlight to other vehicles is fantastic, the light pattern is just not so good.

My fan thermo-switch went bad on me and I had already parralelled it with a manual switch, then when I installed the Baddann scoops from exactrep I found that the scoop hits the bottom of the factory thermo switch and was rubbing on the connector and was going to short the whole system out so I just got rid of it, judgement call on my part to not have a back up in case I forget to turn the thing on but yesterday was the first time that's every happened, not usual for me to walk away from it while its running


Yellowstone was great, I like Moab and Arches even better....desert rat at heart, but it's all beautiful