painsponge

hi,

I hooked up my battery yesterday, but stupidly, I did not completely secure the terminals. After I started the car, one of the terminals slipped off and the battery became disconnected. I heard the horn beep once and the engine died.

Afterwards, I was able to start the car. But I haven't had time to test any of the electronics in the car (power windows, roof, cruise control, etc). Has this ever happened to anyone else, and what are the chances that I may have done any damage to any of the electronics?

Thanks,

joelzeller

Which terminal fell off? Positive (towards front of car) or Ground (towards rear of car)?

painsponge

if i recall, it was the positive terminal that came off

s2000ellier

its fine

joelzeller

Like S2000ellier said, you are fine if the car starts.
If the positive cable touched ground while the engine was running, it might have been possible blow a fuse (maybe the 100A?) since the alternator would be powering the +B line.
On the other hand, i'm pretty sure the alternator only generates ~100A max, so it might have just created a quick short through this fuse without blowing until the engine stopped/alternator stopped and stopped producing power.
Still not sure why the horn beeped though...

Anyways, if the car starts, don't worry about it. Make sure to tighten them down next time.

painsponge

Thanks for the help gentlemen

engifineer

It should not have died unless it touched something. Car should run with just the charging system powering it once started. .I am guessing though that the cable either touched the other side of the battery ,or if it was the positive terminal it could have touhed something metal and shorted the power side which is why the car died and possibly why the horn beeped. But if it starts and runs and runs fine with no symptoms of anything wrong I would say it is probably just fine.

cosmomiller

That is what I thought too. It should have kept on running with a normal electrical system. However, with the positive touching anything on the car (which is grounded to negative) something could have been affected.

I would double check the fuses. However, I might be inclined to disconnect the battery one more time, being careful holding the disconnected end (recommend negative) to see if the engine will still run. If not, you need to run diagnostics on the alternator.

zeroptzero

I remember my terminal cables coming loose once as I forgot to tighten them and I was on a test drive after some parts installed. When I got home and popped the hood the cables were not connected to the battery anymore. The car ran perfectly fine, and I had no idea of the loose cables until I got back home, they were connected when I left the home but surely came loose after hitting the first bump at the end of my driveway more than likely.

painsponge

This is very interesting. I'm fairly certain that it was the positive terminal that came loose. I also double checked and it is very unlikely the loose end would have come in contact with anything else on the car. There just isn't anything in the vicinity for it to touch.

I distinctly recall the horn beeping once before the car died, it was kinda odd. In any case, i have since tested most of the electronics on the car and it all seems to be fine. I haven't been able to test the cruise control though as my car is on jack stands right now. Hesitant to disconnect the battery one more time while the engine is running.
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