|Posted on Wednesday, September 30, 2015 - 11:39 pm: ||
Has anyone else had this problem. I ride my 2008 1125R regularly/200 miles a month average. Normally starts every time. Some time with battery light coming on for a very short time after start, then goes off.
Last week I rolled the bike out of garage, turned the key, and NOTHING! I temporarily connected a different battery and placed my battery tender on it over night. Next day, started the bike and placed a meter on it while idling and showed 13.7 volts. I then disconnected the negative cable and placed a test light between the negative battery cable and the battery with key OUT of ignition. The light LIT UP. A friend told me that it may be the instrument cluster going to ground, but told me to go here to see if anybody else has had this same issue and what was the fix.
Any help is appreciated. THANKS.
|Posted on Thursday, October 01, 2015 - 01:06 am: ||
Had a service truck do the same thing, would die over night even when the main fuse was pulled. Another mechanic took the pos wire off the battery and placed a 12 volt light between the cable and battery post and it lit. Said the regulator in the alt was shot and draining the battery. Replaced the alt and never had the problem. So I'm guessing the regulator/rectifier is shot. I'm sure you can do a search for testing it if you don't have a service manual just to make sure. Let us know how you make out?
|Posted on Thursday, October 01, 2015 - 12:08 pm: ||
The classic method of checking is to take the negative cable off at the battery. With your multimeter set to amps, connect one lead to the batt negative terminal, the other to the negative cable. Then, leaving everything off, start removing fuses one at a time, until the amp reading drops. That will be the circuit to be investigated. A wiring diagram helps.
FWIW, I helped a friend diagnose the same problem on an ATV. When the fuses had all been checked, the amps had not dropped. Then started unplugging various bits, and the the culprit turned out to be the voltage regulator. The friend had dismissed that as an issue because the battery was charging normally when running; one of the first things he checked. Installed a new voltage regulator, and the amp draw remained in the .03 area, instead of the much larger draw with the bad regulator.
Hope this helps, Dave
|Posted on Monday, September 05, 2016 - 12:17 am: ||
You were correct. Replaced the voltage regulator and all is well. Thanks for your help.