# auto battery/electronics question **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 26, 2011, 6:29pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202 "2011-08-26T18:29:40Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![janeslogin](https://avatars.discourse-cdn.com/v4/letter/j/df788c/32.png) [@janeslogin](https://boards.straightdope.com/u/janeslogin)\ **Post date:** [August 26, 2011, 6:29pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/1 "2011-08-26T18:29:40Z")
1983 Nissan Acura was apparently left running in the driveway and ran out of gas and left unnoticed for several days. When it was discovered we could find no electronic features had been left turned on. There was no electronics working anywhere. None of the electronic features wold work. The battery tester showed 2.1 volts. A quick charge and addition of some gas and everything seems fine. Why would allowing a car to run out of gas setting in the driveway with no other electronics on discharge the battery? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 26, 2011, 7:11pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/2 "2011-08-26T19:11:16Z")
If the battery discharged all the way down to 2.1 volts it has likely suffered permanent damage. It may start your car, but it is probably operating at a reduced capacity and may not start the car when it gets cold out. I’ve never seen the electrical system in an 83 Acura, but most cars of that era had an engine computer and an electronic ignition system of some sort that would kill the battery fairly quickly, as well as perhaps a few monitoring things for emissions controls. You’d probably have to go way back to the 60’s to find a car that wouldn’t kill the battery under those conditions. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [August 26, 2011, 7:27pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/3 "2011-08-26T19:27:11Z")
A Nissan Acura? anyway, if the key was on (which it would be if the engine was running and allowed to run out of gas) the stuff that keeps the engine running is still powered. Stuff like the ignition coil(s), ignition module, etc. And an '83 most likely wouldn’t have any low-battery cutoff features, so it’d drain every last bit of charge out of the battery. ---
**Author:** ![thelabdude](https://avatars.discourse-cdn.com/v4/letter/t/dc4da7/32.png) [@thelabdude](https://boards.straightdope.com/u/thelabdude)\ **Post date:** [August 26, 2011, 8:07pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/4 "2011-08-26T20:07:47Z")
> [@engineer\_comp\_geek](#): > > I > > You’d probably have to go way back to the 60’s to find a car that wouldn’t kill the battery under those conditions. Oh, they had points. I just checked my ancient truck, 57 ohms to ground from the ignition circuit. I think most of the lights on the instrument panel these days are LED’s, but an 83 would be bulbs. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [August 26, 2011, 8:24pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/5 "2011-08-26T20:24:39Z")
> [@thelabdude](#): > > I think most of the lights on the instrument panel these days are LED’s, but an 83 would be bulbs. Yep. Once the engine dies, you have at least three dash lights lit, possibly four: -low oil pressure (engine not running, the sensor detects zero oil pressure) -alternator warning light (lights when alternator is not producing the expected 14+ volts) -check engine light (since the engine isn’t running) -low fuel light (if car so equipped) Those alone would eat up the battery over time. Possibly also the HVAC blower was left running? This would also consume electrical power. **engineer\_comp\_geek** has already mentioned the engine electronics that could consume power as long as the key is turned on. ---
**Author:** ![Marconi\_N.Cheese](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@Marconi\_N.Cheese](https://boards.straightdope.com/u/Marconi_N.Cheese)\ **Post date:** [August 27, 2011, 2:57am UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/6 "2011-08-27T02:57:01Z")
> [@janeslogin](#): > > 1983 Nissan Acura was apparently left running in the driveway and ran out of gas and left unnoticed for several days. > > When it was discovered we could find no electronic features had been left turned on. There was no electronics working anywhere. None of the electronic features wold work. The battery tester showed 2.1 volts. A quick charge and addition of some gas and everything seems fine. > > Why would allowing a car to run out of gas setting in the driveway with no other electronics on discharge the battery? Obviously you have your answer, but I’m curious about the circumstances that allowed this to happen. None of my business of course, but it sounds like an interesting story. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [August 27, 2011, 4:12am UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/7 "2011-08-27T04:12:53Z")
On many cars, leaving the key in the OFF position (between ON and LOCK) only powers the radio and clock, but left there overnight (even with the radio off) it will drain the battery to the point of not starting. With it in the ON position for several days, I’m surprised it wasn’t at zero volts. Nevertheless, this episode surely shortened battery life and I agree it would be wise to replace it. Now what, pray tell, is a Nissan Acura? Is it anything like a Dodge Ford? :smack: ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [August 27, 2011, 1:54pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/8 "2011-08-27T13:54:44Z")
Naah, it’s more like a VW Chevy. ---
**Author:** ![janeslogin](https://avatars.discourse-cdn.com/v4/letter/j/df788c/32.png) [@janeslogin](https://boards.straightdope.com/u/janeslogin)\ **Post date:** [August 27, 2011, 4:43pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/9 "2011-08-27T16:43:30Z")
> [@Gary\_T](#): > > … > Now what, pray tell, is a Nissan Acura? … Apparently the car is a 2003 Nissan [Something with an A…] > [@Marconi\_N.Cheese](#): > > Obviously you have your answer, but I’m curious about the circumstances that allowed this to happen. None of my business of course, but it sounds like an interesting story. Car is used infrequently. As best the situation can be reconstructed it was parked in a driveway out of view upon return from the grocer and was forgotten because of a phone ringing. Don’t know why the key was left in the car. Discovered several days later. No likely-hood of anything exciting like a neighbors kid joyriding or any such. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 27, 2011, 5:08pm UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/10 "2011-08-27T17:08:10Z")
> [@janeslogin](#): > > Apparently the car is a 2003 Nissan [Something with an A…] I’m guessing Altima. A 2003 car is going to drain the battery more quickly than a 1983 era car. They put a lot more electronic controls into modern cars. ---
**Author:** ![Marconi\_N.Cheese](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@Marconi\_N.Cheese](https://boards.straightdope.com/u/Marconi_N.Cheese)\ **Post date:** [August 28, 2011, 4:11am UTC](https://boards.straightdope.com/t/auto-battery-electronics-question/594202/11 "2011-08-28T04:11:42Z")
> [@janeslogin](#): > > Apparently the car is a 2003 Nissan [Something with an A…] > > Car is used infrequently. As best the situation can be reconstructed it was parked in a driveway out of view upon return from the grocer and was forgotten because of a phone ringing. Don’t know why the key was left in the car. Discovered several days later. No likely-hood of anything exciting like a neighbors kid joyriding or any such. Ah, got it. Thank you.