I've got a real head scratcher for ya'll. I'll be as descriptive as I can here. Bike is a 2008 Heritage Softail Classic, 76,000 miles, it has the fuel pak and vance & hines long shots pipes and that's all the mods I know about. I was riding down to southern Missouri last Sunday to view the eclipse the next day, about 10hrs total. About 1 hour from my destination, it felt like one cylinder stopped firing for a few seconds, it got sluggish but could still keep speed, then came back to full power and nothing else happened that day. The next day after the eclipse, riding home, I got about 30 minutes into the ride and again it felt like a cylinder was missing, kinda like I was running out of gas (started the ride with full tank), rode like that for 5-10 seconds, then it came back to normal and I kept going. Another 20 minutes or so after that, it did the same thing again, for longer 20 seconds or so, this time it was accompanied by the speedometer going to 0 and the 6th gear indicator went out. It happened a third time maybe 15 minutes later, same thing as before, lack of power, speedometer to 0 and this time the throttle became unresponsive, I started to pull over on the side of the highway when all the sudden it sprang back to life and I was off and running until about 15 minutes later and all the same symptoms came back, I threw on the flashers and took the exit that just happened to be there. The bike completely died on me while coming to a stop and the was unresponsive to the starter button when trying to get it going again. Luckily a gas station was down the hill so I just rolled/coasted it down while off to do some investigating.

Rolled into the gas station, to a pump and topped it off, it took about 2 gallons, so it had plenty of gas (5gal tank). Still unresponsive to the start button, and the neutral light and oil pressure light were looking dim, like the battery was weak, but the flasher indicator lights were as bright as normal. I rolled it to an empty spot and tried turning off the flashers but they would not cancel, ignition was on but while the "N" light was dim I couldn't cancel the flashers. I immediately checked fuses and for a good ground connection, everything seemed fine, but no amount of wiggling of wires made a difference in the dash lights, and I couldn't get it to start. The CEL also never came on. I called a family member who had a truck I could borrow so I could load the bike up and still get home for work the next day. While waiting for the truck, I put it all back together and switched it on every now an then to check, I got the same result a few times, then out of nowhere the dash lit up like normal and the bike started and idled without issue, I could finally cancel the flashers. Knowing I didn't do anything to make that happen, I knew it would die on me again if I took off, so I waited for the truck, loaded it up and drove it home.

Starting my investigation in the garage, it's been tough since I can't get it to replicate the issue or dim the instrument panel lights. It starts just fine in the garage. It did have three codes stored without the engine light on, P1353, P1356, and P1357, all related to no combustion in the cylinders. Where I'm at:
I've got new plugs and wires on the way since it needed them anyway, but I can't see how those would cause weak voltage to the instrument panel.
I cleaned the ignition switch and tried simulating a bad connection through it but also could not get the panel to dim, so I don't think its that.
The vehicle speed sensor seems to be working right, I had the multimeter on it checking voltages while spinning the wheel.
I Ohm tested the plug wires and ignition coil and it checks out. I even ohm checked while heating it up with a heat gun to see if it was heat related, and it stayed in range.
Voltage regulator is putting out 14v, 14.3v with revving, I'm happy with that.
Battery was a little low but was to be expected, I've had it on the charger for a couple days now and will have it load tested. It's a 2.5 year old AGM that stays on a tender over the winter, this would be an early failure if it's the battery.

The way it seemed to affect multiple system initially made me think bad ground, but the flashers staying on strong make me think no. I'm just stuck on the fact that the flashers seemed to be getting full power while the "N" light and module controlling flasher input seemed to not, and they use the same ground (according the the diagram I have) and come out of the TSM. And the fact that condition prevented the starter from spinning up. I know ECM's rarely go bad but it seems to be my best guess at this point, I'm more hoping there is a failing cell in the battery or something that could explain it all. I just know it's going to leave me stranded again if I can't find the problem, it's got me hesitant to ride it, I can't count on it.

Anybody got ideas of something else to look at?

 

1. Check your MaxiFuse to make sure it is seated correctly and has no corrosion.
2. Check your other fuses also.
3. Check to ensure all battery connections are tight both at the battery, frame grounds, and starter.
4. May be a loose connection, maybe not, check all connectors for corrosion etc.

NOTE:
The above information, while credible, is worth what you paid for it and should not be considered gospel.
Do due diligence, research and have a H-D Field Service Manual before working on your bike.
You will probably have many opinions and suggestions presented; make sure you research the person providing the helpful information as there are some who provide good information that is useful and some who speak out of other orifices with gibberish. You will figure out this quickly.

 

sounds like it may be battery related. you rode a little over 9 hours before the first incident then started to have the same issue more frequently.

 

1)change the fuel filter in the tank.
2)check all ground wires.
3) while the bike is on the charge does it give trouble? if not , get a new battery
4)check for pinched wires under the fuel tank
5)Very rare but a failing TSSM