Do you turn your radio and A/C off before turning your car off?

[mb]

A few of my friends (all of whom happen to be female) always completely turn off the radio and air conditioning before turning off their car.

Now, I can understand turning the A/C down so it's not blowing hot air when you turn the car on, and I can understand turning the volume down on the radio if you had it up really high so it's not blasting when you turn the car on, but I don't understand why they completely turn them off every single time.

I've asked two of them why, and they said they really didn't know, it's just something their parents do. Was this something that at one time needed to be done? I asked my parents and they said they don't ever remember doing that. Does anyone here turn them off? If so, why? I'm curious.

 

[P0pinjay]

I do, could save some strain on your starter if it doesn't have to crank the A/C compressor as well as the engine...don't have any figures to back it up but it makes sense in theory at least.

 

[thomsbrain]

Originally posted by: P0pinjay
I do, could save some strain on your starter if it doesn't have to crank the A/C compressor as well as the engine...don't have any figures to back it up but it makes sense in theory at least.

the compressor won't switch on until the car is already running, anyway.

i don't think there's any point to doing this except for saving yourself the sometimes-startling blast of air and noise every time you turn on the car. especially in the morning, the last thing i want is my stereo cranked up when i first go out to work. as for the HVAC, it's all automatic, so I set it and forget it. It slowly ramps itself up to the right speed and temperature regardless of how it was running when I shut the car off. Back when I had a manual control, I used to turn it down or off, though.

 

[LTC8K6]

My radio won't be at full volume anyway, even if left that way. It resets to halfway when you turn the car off, so you'll never get surprised by it.

I turn the A/C off out of habit, and because the knob looks neater straight up and down.

 

[getbush]

In modern cars with auto climate controls it's not much of an issue. My car won't crank the a/c fan on a 90 degree day until the a/c has had time to get cold.

 

[Apex]

I usually turn the AC off a few miles from my stop to keep parts from collecting condensation. It's just habit though, as AC parts are pretty stout these days. Radio I leave alone.

 

[ponyo]

I turn both off too. I don't know why. Habit I guess I picked up from my dad.

 

[krunchykrome]

I turn my radio off, just because I don't like to hear the radio come on full blast when I start my car. Especially in the morning when I am tired.

But I dont shut the a/c off. My girlfriend has the habit of doing this.

 

[steppinthrax]

It dosen't matter what you really have on before you start your car. The ignition system is designed to shut power off to everything before the engine is started. If you want to do a little test turn your A/C on highest i can go, wipers on, radio on and everything else you can think of. When you start the car those devices will cut off right before the ignition key gets to the starting position. Most systems also won't start any ACC (Accessory) devices until the car's been running for at least 2 to 3 seconds (more then enough to get the alternator to full amperage). The A/C clutch also won't energize for a respectable amount of time for the engine's sake. The radio in most cars also pulls extreamly little amperage v.s. the blower motor, defroster and other devices.

 

[j00fek]

a/c off, not the radio

 

[Kelemvor]

I can't tell if the AC is on until I start the car anyway.

 

[manowar821]

I turn the system volume down, and turn my fans off no matter what. I don't like air being blown in my face when it starts. My stereo is on all the time, though.

I don't understand why they'd turn it off.

 

[GTaudiophile]

Yes, I always "reset" my car back when I had one such that everything would be at "default" next time I got in.

 

[Caecus Veritas]

i always thought it was not to strain the engine when you're warming up the car... if you have the a/c on when you first turn on the car, the engine will be reving higher. another thing i don't do in the morning is rev beyong 3 rpm until the engine is fully warmed up.

 

[alimoalem]

A/C definitely and usually the radio. reason? some belt or something is f'ed up so if the A/C is on, it definitely squeels. if it's night time (when it's cold) and we immediately turn on the headlights and radio, it squeels. so we let it warm up then turn on the a/c, headlights, radio.

sad, i know. but we have a reason nonetheless

 

[deerslayer]

I turn off my AC, but my car starts hard if I leave the AC on. Radio I just turn the volume down.

 

[NaOH]

I turn off my AC. I thought it would prevent any unnecessary strain. My stereo attenuates the sound and slowly increases volume when i start it up. So no suprise there.

 

[ViviTheMage]

Originally posted by: Apex
I usually turn the AC off a few miles from my stop to keep parts from collecting condensation. It's just habit though, as AC parts are pretty stout these days. Radio I leave alone.

I do the same thing.

 

[soonerproud]

On older cars before computers it took a lot of strain off the battery when staring the car with the AC and the stereo off. On todays computerized cars it really doesn't matter since the computer switches every thing off while you are cranking the starter.

Personally I turn both the AC and radio off. It is just a habit I have that extends into my home that I turn off what I am not using. For me it just keeps thing consistent.

 

[Raduque]

I pause my Zune.

I also leave my lights, air and radio right where they are. Maybe turning down the radio if I was listening to a loud song when I parked.

 

[Pacfanweb]

Unless you have a car that's over 20 years old, it helps nothing to turn off the A/C first. The condensation thing is not and never was an issue, either. The condensation happens, it evaporates. A/C systems don't rust.

The radio, that's just a personal preference...no right or wrong. I prefer mine to not be blasting when I first start the car, though.

 

[OrganizedChaos]

a/c compressors don't have much drag until the high side pressure builds up and i'd imagine the alternators voltage regulator will have the 'field voltage (don't know proper term)' maxed anyway on startup.

 

[Lumathix]

I turn the volume down low before shutting off the car, so it doesn't blast me when I start it next time. As for the AC I never touch it, as mine is a "thermostat" type, where you set it by temperature.

 

[Zenmervolt]

Originally posted by: P0pinjay
I do, could save some strain on your starter if it doesn't have to crank the A/C compressor as well as the engine...don't have any figures to back it up but it makes sense in theory at least.

Modern cars have a cut-out circuit that kills power to all accessories when the engine is cranking, so even if the A/C and radio and such are "on" when you start the car, they are not engaged until you let the key spring back into the "Run" position after the engine has started.

ZV

 

[Zenmervolt]

Originally posted by: soonerproud
On older cars before computers it took a lot of strain off the battery when staring the car with the AC and the stereo off. On todays computerized cars it really doesn't matter since the computer switches every thing off while you are cranking the starter.

The computer doesn't turn a damn thing off. It's strictly to do with how they are wired electrically at the ignition switch. No microchips necessary.

ZV