Won't run without battery connected...

[Doug Huffman]

Originally Posted by A B Able Truck

A good idea, especially for the short commute driver.

What Causes Car Batteries to Fail? – Battery University

***

Thanks for the citation link URL. I thought that I had read every page at Battery University, but not that one I discovered.

[ard]

Originally Posted by wsmeyer

You people are really paranoid. There's no black magic going on inside a battery. When the engine is running the battery is just a simple resistive load, and not a very large one at that. The radiator fan draws roughly 5 times the amp as the battery and the electrical system has no problems with that cycling on and off.

Correct, nothing magical INSIDE the battery.

Once you understand how BMW manages the battery, and the modules they connect to it, you will recognize that the old days of 'just a battery hanging on a fat cable to the alternator/regulator' are a thing of the past.

[Doug Huffman]

Originally Posted by ard

Correct, nothing magical INSIDE the battery.

Once you understand how BMW manages the battery, and the modules they connect to it, you will recognize that the old days of 'just a battery hanging on a fat cable to the alternator/regulator' are a thing of the past.

+1 Well said.

[wsmeyer]

Nonsense. Disconnecting the battery isn't going to do anything to the electrical system is hasn't been designed to deal with. I'm not saying you should make a habit out of it but automotive electrical systems are extremely durable.

[jfoj]

Originally Posted by wsmeyer

Nonsense. Disconnecting the battery isn't going to do anything to the electrical system is hasn't been designed to deal with. I'm not saying you should make a habit out of it but automotive electrical systems are extremely durable.

Oh, well.

[bmrboi2]

Reading that Battery University article, would it be wise to shake our batteries periodically to prevent premature discharge?

[jfoj]

Just take your X5 out and roll it over a few times every year and it will keep the battery young!

[A B Able Truck]

Originally Posted by wsmeyer

Nonsense. Disconnecting the battery isn't going to do anything to the electrical system is hasn't been designed to deal with. I'm not saying you should make a habit out of it but automotive electrical systems are extremely durable.

Best response stolen from another thread;
Your battery does more than just provide electrical current. It shorts spikes and transients to ground. Removing the battery from the circuit allows those spikes and transients to travel which could damage circuits in your vehicle. (ECU, speed sensitive steering, memory adjustments, cruise control, stereo, etc. etc.)
I've never been struck by a bus but I've never stepped in front of one either. Some mechanics still do this - some are lucky and some not. But would one ever admit (and pay for) their mistake?

[jfoj]

[onebad7up]

Replaced the alternator tonight and all is well. System charging.

Thanks to those who offered constructive advice.