Stop light 10A fuse melted!

[Drano]

Hi everyone, I took the Mighty Smurf for a good run on the back roads early yesterday, in search of croissants.. 

Then later in the day I put the battery on charge (haven't driven it for a few weeks, so wanted to keep it happy) - after a few hours the (smart) charger had finished its work, and the battery was fully charged.

As I went to back the car into the garage, I noticed the brake lights weren't working, and the high beam indicator on the dash was on when the lights weren't even turned on. Indicators also worked OK.

This morning in the good light of day, I've opened the fuse box and found the 10A STOP fuse melted! 

I'm guessing the battery charger (which was on the battery in the car, not taken out of it) has done this? Surely not the speedy (80-90 km/h) run in the early morning?

I've tried to pull out the remains of the fuse, but there's still melted gunk in there. I can't get a good enough look at whether the fuse point has melted too. Anyway, shall get the auto elec to check out the fuse box issue properly.

[Brayden]

Did you disconnect the battery before you started charging it?

[Drano]

No, I didn't disconnect it.. I've charged it up before with no problems - surely the charger isn't more powerful than the alternator?

[Brayden]

No it isn't, but most chargers specify disconnecting the battery (at least the -ive lead) when charging.
The only thing that could melt a fuse designed to pop is too much current over a prolonged period, into shorted wiring.

[Drano]

Ah, well lesson learned there.. Thankfully just a fuse

[Brayden]

I'd check the circuit for any shorts, just to be safe.

[Drano]

Update on this - I had the fuse box checked out at the auto electrician, and they tidied things up after the melted fuse.

They said the charger wouldn't have enough power to do any damage to electrics.

They said there was a faulty brake switch, which probably left the brake lights on the whole time I was out the other morning, therefore heating things up electrically.

Hmm, anyway all good - but I'll keep the battery isolated when charging anyway, just in case.