Bike: 2018 Husqvarna FE350

I have an intermittent battery drain. Sometimes when I park (turn bike off and take out the key) the bike for 12 hours or so, the battery will be dead. Sometimes, the battery will be fine, and the voltage will have not dropped at all.

I've replaced the battery a couple times, and had the newest one tested. The battery is perfect.

Also, it seems that every time I disconnect the battery, then reconnect it, the drain is no longer present. In order to get the drain to appear again, I have to fire the bike up. Even then, sometimes the drain won't appear. It is quite intermittent, and makes it challenging to diagnose.

I've taken it to the mechanic and they claimed it was a loose battery terminal. It wasn't. I've checked every fuse. They are fine.

I was thinking about just sticking a switch between the negative battery terminal and the black wire that is connected to this negative terminal. When I'm not using the bike I would flip the switch and effectively disconnect the battery from all circuits rendering the effects of the battery drain null. This was the switch I was thinking of buying

Is this a viable strategy? Also do I need to use heavier duty wires/switch if I stick a switch in this location to accomodate the amp draw?

  • 1
    Welcome to Motor Vehicle Maintenance & Repair! Nov 30, 2018 at 2:13
  • 2
    This bike, if it is 2018 is still under warranty, so any major changes like you suggest will invalidate that : are you sure you want to do that? Best get them to fix it properly and/or take it to another dealer...
    – Solar Mike
    Nov 30, 2018 at 6:53

1 Answer 1


Your strategy should be to get the dealer to fix your bike. They should be able to test for a parasitic battery drain by putting a multimeter in-line between the battery feed and the terminal (that's a test you can do yourself as well). Small problems can develop into big problems over time, get it dealt with now while its still under warranty.

Installing a battery isolation switch won't invalidate your warranty provided you pick the right one. You want one that doesn't require cutting any wiring and is designed for the load. The switch you've picked is not designed for the load, which could lead to big problems - it could melt on you and cause damage. Look for something that bolts in.

However, it's worth repeating you should get the dealer to find the source of the problem and fix it, a battery isolator is a stopgap.

  • I went to the dealer. Described the issue in detail (verified there notes) and they returned it a week later claiming it was a "loose negative battery terminal" and charged me $80 (for 30 minutes of labor) for this diagnostic. The problem is, in order to put a multimeter inline with the battery, the battery needs to be disconnected. The moment this happens, the battery drain disappears. I can reconnect the battery to the bike and the batter'y voltage never drops. Thanks for the note on the switch Ill use one with better suited for the load if I go this route.
    – steve
    Nov 30, 2018 at 18:34

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .