OK. That only somewhat rules out the ACC circuit, but not totally. I assume you have a battery charger, you'll need one before this is over I'm sure.

That's where the 4 breakers are - inside the fairing, under and in front of the speedo/tach bucket. Main breaker on the oil tank or under the seat. I don't know if you can get to them by removing the headlight assembly or if you'll have to remove the outer fairing and don't know if you're willing to go there. It would be handy to know which breaker is kicking and might ultimately save some time.

But try these steps - turn everything on, engine off. Walk around and look for ANY lights not working or extremely dim. Turn signals, fender tips, tail, gauge lights, brake light with both foot and lever, etc. Also, there are 4 back lights in the speedo bucket and hard to tell if one is not working unless it's fairly dark. They are at 2 and 5 o'clock on the speedo side and 10 and 7 o'clock on the tach and all are near to the center strip in that cluster. What I'm getting at, may be a light wire pinched or a bulb missing somewhere causing the short.

Also chance some wiring for the not present siren and cop lights is pinched or twisted together like they shouldn't be. Without knowing exactly what has been done to the bike between the time everything worked and this issue started, I'm just guessing.

 

I tried to enlarge your signature pic and still can't tell which version Police bike you have. I don't see a batwing. Post up a photo of you instruments (speedo dash).

This may be a lot more simple than I've been thinking / making it out to be.

 

No batwing, windshield only.
This was an Indiana bike that local prior owner said had a sidecar before he purchased.
Possibly At connection for side car wiring?
Once tried to lift gauges, but would only lift about 2”
I don’t have an FSM but I have a factory parts book, I’ll look at gauge fastening.
Thanks for your help.
I’ll try to get someone here to help w the pic.

 

OK, great. No photo needed, I can see it with my eyes shut

Yes, much easier to "get in there" with that dash setup. You have to remove the tripometer ****. It takes a fairly long #0 phillips driver. Make sure you get a good engagement feel before trying to remove. It's a tiny screw and the slots will get dirty. If needed, wrap a rag around it, give it a blast with brake clean / tube to clean the slots.

Get that out, remove the ****. Then you have to get it up high enough to unscrew the speedometer cable. With that disconnected, the dash will lift up and you can set it back on the tank, or disconnect the 12 pin connector and there's usually one more single connector, (maybe 2 singles since it's a Police model) and set it out of the way.

With that out of the way, the breakers are right there. Left to right - Acc, Lights, Ign, Constant.

PS. You might have to, or be able to un-screw the speedo cable from underneath. Turn bars far right and look for it. Sometimes you can, sometimes not. Depends on the cable.

 

Headlight, yellow guide lamps, f/fender tip, tailight, rear fender tip all cycling on and off w breaker in gauge cluster.
T140V tank since I was there.

 

Beautiful bikes!!!

Definitely on the lighting circuit then. The voltage draw of the short and breaker kicking is what was causing the dim/bright of the dash bulbs. They are on the Acc circuit.

So, it's just a begin hunting thing. You might start under the left side cover. The main harness connects there to everything rear of the seat. Un-plug that (or those) connectors and that will tell you if the short is forward or toward the rear of there. I honestly do not know where or how a sidecar harness connects in to it all. What or where ever, it sounds like a dead short. Wire pinched or rubbed the insulation off. Good luck.

Thanks again for the photos. Awesome to see one that old, original and so pristine.

 

Any chance you could undo the speedo cable at the wheel.
Might give you some extra slack at the top to undo the cable there.

I did something like that back down the line just can't remember which bike we were working on.

Best of luck

WP

 

I had the left cover off a while back, don’t remember seeing any real wiring going on under that, just air lines.
Any chance mine under the plastic frame cover just below seat?
You’re leaning toward it having short in lighting circuit, as opposed to a bad ground or weak breaker, then.
Thanks for all the input.
Speedo cable is likely limiting lift of gauges, not wire connectors?

 

I'm 99.99% certain of that. The harness will allow it to be raised 12" or more. Sometimes they'll come up enough to disconnect the cable, but usually not. Loosen or remove the nacelle (# 33) and imagine a straight line thru the center of the speedo needle. That's where it is on the bottom. I generally use one finger of each hand to get them loose. It's tight up in there, and you can see it, but not with a hand up in there.

Anything is possible, but with all the lights cycling off with a breaker, that's almost a given it's on the light circuit. Considering the low miles especially, I can't help but think it's some bit of wiring that was done for the sidecar that may not be correct, or was haphazardly disconnected causing a short. But no guarantee it was even electrically connected.

There's so many places a short could happen, impossible to list them all. The wires going to the fender tip lights run thru metal sheaths and are easily shorted if they have ever been disturbed. Some people run wires under the chrome saddlebag support rails on each side of the rear fender and have seen issues with that a few times. Beyond that, the list goes on forever concerning possibilities.

If you were able to spot any particular bulb that did not light during the breaker cycling, or one that was obviously dim, that is a good place to start feeling and tracing the wires.

 

After a good long wait for a slot at an Indy nearby, bike is finally done.
This shop still had my name in their computer from buying something there 30 yrs ago!
Fault was pinched wire coming out of r/s blinker.
If it had teeth, it woulda bit me.
Bike had a good going-over, wheel bearings were found not serviced, after tires were last replaced.
Pilot jet down to 46 from a rich 50.
All fluids.
Thanks for help, all, especially T150!