hello all and thanks for viewing my post.i have a 2003 trail boss that i am working on for a friend of mine and the issue i am having is the quad does not appear to be charging the battery.i have metered the voltage at the battery and regardless of when the motor is at idle or reaving the voltage stays the same(around 14 something volts).i can't get it to change any voltage readings at all.my friend tells me that it runs ok until he turns on the lights at night and then it runs down the battery.i have charged the battery and it is a fairly new one.do any of you guys know some tests i can try to run or if you fellas have seen this before maybe you can tell me what this problem is.thanks again guys for all your help!! Jerry

 

i would check grounds on the rectifier first...then check connections coming from the stator to the rectifier to the battery. cheaper to check the easy stuff first then move on to more monetary solutions

 

I have checked the grounds and it seems ok.should i be seeing some sort of voltage change when the motor is racing?if so ,i'm not.thanks

 

Should be 12.5 or so shut off and 14 to 14,5 when reved up a bit, check the connections at the selenoid, take the battery cables off and check nuts behind them, clean everything before you put it back, if its showing 14 volts it is charging, maybe not enough to run the lights though.

 

I have checked the voltage and now I am getting some funky readings.With the engine running,It will read 11.30 volts and then drop to 10.54 or so then go back up to 11.30.Could this be the regulator or is this normal?For whatever reason i have still not ever seen it hit 14 volts with the engine revving,and when you turn on the lights it drops even lower.All connections seem fine i have cleaned them with contact cleaner.I'm starting to think this may be an expensive fix for my buddy!Ideas????

 

If battery is new or load tested good and charging erratic as you say then possible the black module under the front cover(ecm) is going out. Its not on any recall list or has an updated replacement that I'm aware of,BUT its still the old Chinese black module! #4010697 (I believe thats the right number? Main purpose is for charging and fan operation

 

that may very well be the problem because i have not heard the fan come on yet and it has idled at times for 45 mins.i will check it out.thanks alot!!