Hey all, I've received greathelp on this forum before so I'm going to the well of expertise again.[/align]The other day my 02 UC wouldn't start, no click no nothing.I checked the battery and it was [/align]dead. I then used VOM to test for a wiringshort and betweenpos battery cable and frame ground [/align](or the neg cable) there was a direct short (continuity) between the two. I traced that down to the air horn circuit and unplugged the horn relay. Now when I test there isn't direct continuity anymore,but there is like 44meg ohms and if I hold the VOM leads on the battery cables the ohms steadily decrease.I put the charged upbattery back in the bike and when I turn the switch to on (without bike running)I hear a terrible static/buzzing/hum type noise coming from the speakers. The bike starts fine, but still has the noise. I found nothing in my service manual. Any ideas????[/align]

 

wow, lots of hits, but no takers yet. Electrical problems are the worst!!!
To follow up, I tried looking over as much wiring as I could to see if something is loose, all seem clean and tight from what I could tell.
Let me be clear, the noise is present when the ignition is turned on, kill switch can be on or off, radio can be on or off doesn't matter, and the bike is NOT running. If I press the start button bike jumps to life but the noise is still heard.

 

Wow, strange problem. In the interest of narrowing down the problem, with the noise sounding, start pulling one fuse at a time until noise quits. Each time you pull a fuse, put that fuse back inthen pull another one. Hopefully this will get us in the ballpark as to what is all on the circuit of that fuse and then we go from there. Possibly a bad ground somewhere causing a back circuit thru another component which is rebelling. Does your serv manualhave circuit diagrams?

 

thx geargrinder,
great idea, isolate one circuit at a time. I'll be pulling fuses 1 by 1 tonight.
Any worry that pulling a computer fuse might harm the brains??? I'm also
going to open the fairing and take a look see.

 

No problem, the ECM has a non volatile memory meaning that you will not loose any programs or data doing the fuse thing. I would have ignition switch turned off each time you pull a fuse though to prevent voltage spikes to ECM.

 

Thx Geargrinder,
I've went through, bar controls, faring to fork to frame grounds, wiring, and speakers. On the back of the radio there are 2 multi wired plugs, one has bunch of crap + rear speakers, the other has the same + front speakers, if I pull either of these the noise shifts to the plugged in speakers.. I did pull the radio fuse yesterday and with no power there is no noise. This makes me lean more to the radio as the problem. One other thing, while having power to the radio I tested and probed around for several minutes and then I put my hand on the side of the radio and that case was darn near red hot. I would think this would blow the fuse.... needless to say, I am keeping the fuse out. Anyone know of a place that test and repairs or replaces HD radios? BTEW - Battery has held a charge this whole time.

 

Check the radio ground by checking for voltage between the radio and the battery negative pole. if the ground floats at all, the radio could be picking up static from the ECU or, if you have fuel eijection, the fuel pump.