Any advice finding a short?

[tweety]

hey guys. i've been having some charging troubles on my bike, and using the honda service manual's charging troubleshooting flowchart, i found that the bike failed the battery current leakage test. it told me that i've got a short somewhere. it literally says: "you've got a short, now go find it."

at that point i had to run off to work, so i thought i'd post, hoping yous could help speed up my search.

there is a whole whack of various wire connectors around the battery and all over the bike- so i could spend days removing parts and disconnecting them all, while testing the current leak each time. is there a faster way? perhaps removing fuses from the fuse box? on most bikes is there a usual cause for shorts?

thanks.
dave


PS: one of the symptoms before dying was the speedo & tach resetting to 0 while riding when i touched the brake- i figured this was because the brake light took some power & the instrument cluster wasn't getting enough juice. but i suppose it could also mean I could start my search for shorts at the instruments or brake light connectors... ?

[dre_2k2_f4i]

This term is thrown out whenever a Honda has electrica problems: rectifier/regulator?

[tweety]

yes, that is a typical problem, but i don't think it's mine. i already passed that branch on the flowchart. disconnected reg/rec & retest battery current leak. leak still exists, so i know the leak didn't come from r/r.

[dre_2k2_f4i]

Sounds like you will have to check every connector to look for burnt-out connecters. Clean all the contacts while you're at it, and use contact grease to prevent corrosion. Then go through all the wiring, especially anything that might rub against body work or may be pinched and may have worn through.

Your idea of disconnecting fuses might help to isolate the area to investigate. Test your battery's voltage at idle. Turn it off, disconnect a fuse, measure voltage at idle again. I am not sure what the differences should be, though.

[Philo]

So the charging voltage is OK??? Did you get around 14.5V accross the battery above 5K RPM? If so I think you're saying that it's just leaking current and draining the battery while sitting. So, no charging problem, right???

Check around the steering head for pinched/rubbing/worn cables. Then check the brake light circuit. The front brake should activate the light with a sensor either in the master cylinder or a junction along the brake line. I'd check that connection first. Then check bulb/socket/connections for the rear brake light itself. Then do what dre said. doo wha hee saaayyyyyysss. :-p

[tweety]

Originally posted by Philo
So the charging voltage is OK??? Did you get around 14.5V accross the battery above 5K RPM? If so I think you're saying that it's just leaking current and draining the battery while sitting. So, no charging problem, right???

Check around the steering head for pinched/rubbing/worn cables. Then check the brake light circuit. The front brake should activate the light with a sensor either in the master cylinder or a junction along the brake line. I'd check that connection first. Then check bulb/socket/connections for the rear brake light itself. Then do what dre said. doo wha hee saaayyyyyysss. :-p

Actually, it did fail he charging test here are battery voltages:

bike off: 12.8 V
bike on at idle: 12.2 V
bike on at 5000 rpm: 12.4 V

So there _is_ a charging problem, but I (mistakenly?) assumed the current leak would be causing the charging test failure... So I guess I have two problems: charging problems (probably R/R) and current leakage.

I'll try out the advice you guys posted... (wires around steering head, tail light, fuses,... ) and I'm also going over to a friend's place this weekend who also has a bird, and i'm going to swap in his R/R and try the charging test again.

Thanks for the tips, guys...

[Philo]

Quick tip: I would put your Reg/Rec in his bike. If there's something amiss (<--wtf) with the wiring that caused your R/R to go bad, it may do the same to his.

So, yeah, check his off/idle/charging voltages, then pop your R/R in there and see if it changes.

[tweety]

excellent idea. I hadn't thought of that.

thanks! :guitar:

[Caine]

:banana::rockon::banana: