Hey guys,

Kind of a newbie here for posting, but been reading for a while. I have a serious issue that i'm having troubles finding and have spent the better part of 2-3 days testing.

2002 road king.... I just had it at the shop, and they did the true dual header pipes, Thundermax tuner, and changed out my 16" bars for 18" bars. Also did a legend air ride at the same time. Well, i'm having some serious battery drain problems.

I can drive the bike during the day, but if I get home at 10-11pm, and park it in the garage, the next morning the battery is dead. So I've been testing things on it. Completely charged the battery with a slow trickle charger. Disconnected everything hooked to the negative battery terminal and stuck a tester between the negative terminal and the negative cable. The tester does a "flash". Its almost like a turn signal flash. Flash. Flash. Flash. Flash. Constantly does that. So I started tracing things. If I take out the "security" fuse it quits. But I don't have security on this bike. So last night I disconnected the TSM from the wire, and had the battery fully charged. This morning it was dead again. (overnight I left everything hooked to the battery but had the TSM disconnected) So I charged the battery up again today, disconnected all of the connectors behind the headlight for the bars, took off the negative cables, and did the tester again. Low and behold I still have the same "flash" on the tester.

The next thing I did was hooked everything back up behind the headlight, then started disconnecting everything else. By the stator, under the speedo, started taking more fuses out. The only way that flash goes away is if I take out the "security" fuse, or the ECM power fuse. But if you take either of them out, the bike won't start. So I decided to leave it overnight tonight with the battery fully charged, all cables and wires hooked up, but I disconnected the Thundermax tuner. As soon as I unhooked that the "flash" went away, so that's why I decided to try this tonight.

Could the Thundermax tuner have an issue? Or did the shop forget to program something in as far as a battery drain? I'm not super familiar with the tuner, or what you have to put into it. And since it's a weekend, I can't get ahold of anyone at the shop. I'm pretty sure they installed it properly as they have done a bunch of them. And when I picked the bike up, they said there was a real bad battery drain, and I said well I would bring it back, but they have gotten swamped with work, and haven't been able to look at it since. I am hoping to have it figured out this week as I want to put it in a bike show this coming weekend.

So could there be something faulty with the thundermax? Or am I completely off in my thinking or where i'm looking? The "flash" on the tester is bright enough that it's a big draw. I don't have a multimeter handy to see how many amps it's drawing. But i'm sure it's a few!

What else could I check if it's not the thundermax?

Thanks in advance everyone!