Battery Question

sha786 · Post by **sha786** » Mon Feb 11, 2013 2:21 pm

So,

Let's say I was driving along and the negative wire on the battery terminal became loose and came off, would this cut the engine? Or would the car stay on until the next time I switched the engine off and simply not come back on?

Excuse the silly question

Post by **NafemanNathan** » Mon Feb 11, 2013 2:33 pm

Yes, your circuit would be incomplete and you'd loose ignition amongst other things.

Post by **Merlin** » Mon Feb 11, 2013 2:46 pm

Yup you'd be a rolling brick with no assisted brakes. At least with the key still in position II your steering lock wouldnt be on but you would have no power steering. My engine cut off switches (breaks the negavive battery line) will also be my main anti-theft device.

sha786 · Post by **sha786** » Mon Feb 11, 2013 3:15 pm

This is strange as last night I was driving along, stopped at Tesco, went to restart the car and nothing. No hazard lights, no power at all. Opened the bonnet and the negative battery terminal had come off

So that must have been a coincidence that it just came off when I came to a standstill. Scary stuff

Post by **Merlin** » Mon Feb 11, 2013 3:20 pm

Bizarre!

Post by **4thgenphil** » Mon Feb 11, 2013 3:21 pm

see i thought after start the engine/alternator wouls sustain the engine

like race bike, they dont have batteries?!

Post by **NafemanNathan** » Mon Feb 11, 2013 3:32 pm

4thgenphil wrote:see i thought after start the engine/alternator wouls sustain the engine

like race bike, they dont have batteries?!

Do they not?!

Without the negative connected on our cars you're effectively removing the battery from the equation as it needs a complete circuit to effectively allow the power to be drawn from it. That's be like jump starting a car without a battery (which is obviously doable) and then removing the jump leads and expecting it to still run.

Post by **Merlin** » Mon Feb 11, 2013 3:33 pm

You have me questioning it now

For instance the main relay and hot start issues.

Nafe, could it be that it is running purely off the alternator?

Post by **NafemanNathan** » Mon Feb 11, 2013 3:36 pm

I'm trying to think what cables are attached to the negative now

Try it!

sha786 · Post by **sha786** » Mon Feb 11, 2013 3:36 pm

Like I said, I think it came off when I went over a bad pothole but the car continued to run fine.

I wonder if I should test the theory, whats the worst that could happen?