Motoring Discussion > Heated seats battery usage Miscellaneous
Thread Author: a900ss Replies: 32

 Heated seats battery usage - a900ss
Hi,

Does anybody know how long you can have the drivers heated seat on without the engine running and leaving enough juice in the battery to start the car?

I have a Legacy diesel and often need to make calls in the car that can be up to an hour long. In the cold weather I generally leave the engine running so the car heater keeps me warm. I was just wondering if I switched the engine off but put the heated seat on for an hour, would the car still start? I know I could give it a try and see what happens but that could be rather silly if it doesn't start. Any personal experiences most welcome.

a900ss
 Heated seats battery usage - hobby
I only have experience of after-market heated seats and they take a matter of about a minute to heat up, so they aren't needed until I actually get in the car and the engine is running then so battery discharge is irrelevant... I can't say how long the fitted heated seats take to get up to temperature, though!
Last edited by: hobby on Mon 13 Dec 10 at 20:51
 Heated seats battery usage - Iffy
I agree with hobby.

The heated seats in the CC3 are up to temperature in a minute or so - can't see the point of switching then on before it's time to get going.

 Heated seats battery usage - a900ss
Sorry, perhaps I'm not making myself clear. I don't need to pre-heat the car, I want to sit in the car for an hour when it's cold and use the heated seats to keep me warm rather than have the engine running and use the car heater/blower to keep me warm.
 Heated seats battery usage - spamcan61
A quick Google suggests heated seats tend to be in the 45-60W range, so 5A ish from the battery. An hour should be OK assuming the battery is close to 100% charge to start with , but I wouldn't want to start doing that for hours a day, as that's probably 10% of a typical battery capacity per hour.

This is assuming that your heated seats will work with the engine off, I don't think the ones in my Omegas did.
 Heated seats battery usage - a900ss
Thanks Spamcan, that's the kind of info - was looking for. I have checked and they do work without the engine on, I found out by accident and that's what got me thinking.
 Heated seats battery usage - hobby
Sorry 900, I see what you mean now! ;-)
 Heated seats battery usage - Iffy
...I don't need to pre-heat the car, I want to sit in the car for an hour when it's cold and use the heated seats to keep me warm...

Don't think the car will use that much fuel at tickover, so I'd be inclined to leave it running for most of the time, if not all of it.

 Heated seats battery usage - Lygonos
>> I'd be inclined to leave it running for most of the time, if not all of it. <<

Illegal in many locations.

 Heated seats battery usage - rtj70
>> Illegal in many locations.

Even when sat in it?
 Heated seats battery usage - rtj70
I'd leave the car running if a diesel. Even if the battery is okay after an hour you might have to then do quite a bit of driving to recharge it fully. And if you have the seats and other electrical systems on it might take longer still.
 Heated seats battery usage - R.P.
Only illegal in the UK if you leave the car with the motor running...
 Heated seats battery usage - Iffy
...Only illegal in the UK if you leave the car with the motor running...

Makes sense, it would be hard to enforce anything else.

As a responsible citizen, the OP might have concerns about noise pollution, depending on where he's parked.

A decent-sized blanket would help a lot.

 Heated seats battery usage - Zero
I don't know of any car where the heated seats work without the engine running.
 Heated seats battery usage - Runfer D'Hills
>> Only illegal in the UK if you leave the car with the motor running...

Doesn't everyone do that though when they stop at the post box ? I'm probably due a life sentence on that basis...

:-)
 Heated seats battery usage - Zero
You name vill also go ze lizt. Vat is it!
 Heated seats battery usage - Harleyman
On Volvo trucks, the heated seats will not work even with ignition on, unless the engine is running; presumably to avoid battery drain.

Once I've started up, by the time and done my daily walk-round checks, the seat's lovely and warm. I commend this idea to the house, might stop a few of the "one-eyed Jacks" which populate our roads in winter months.
 Heated seats battery usage - legacylad
Good question a900ss. In my 3 previous Legacy estates I never knew you could operate the heated seats without the engine running! Mind you, the latest was a '97 model. Not sure I would risk it myself.
I really miss heated seats in my BM. The cold leather on a morning is no fun. Then again, maybe I am becoming a soft old sod.
 Heated seats battery usage - R.P.
Don't tell him your name Humph !
 Heated seats battery usage - Zero
>> Don't tell him your name Humph !
Ach So

Humph!
 Heated seats battery usage - Runfer D'Hills
It's ok, I now have my two "little tanks"...( oh, and a fallen Madonna with...)

;-)
 Heated seats battery usage - Suppose
>> Only illegal in the UK if you leave the car with the motor running...
>>

The law:

* Section 88 of the Environment Act 1995 and Road Traffic (Vehicle Emissions) (Fixed Penalty) (England) Regulations 2002 allows EHO's to issue the FPN's
* Section 42 of the Road Traffic Act 1988 is the offence
* Regulation 98 of the Road Vehicles (Construction and Use) Regulations 1986 says that the engine must be switched off when stationary (with exceptions)
* Regulation 107 of the Road Vehicles (Construction and Use) Regulations 1986 says that the engine must be switched off when the driver is not present


www.parliament.the-stationery-office.co.uk/pa/cm199293/cmhansrd/1993-01-19/Writtens-5.html
Vehicle Engines

Mr. Redmond : To ask the Secretary of State for Transport if he will introduce legislation to limit the time that vehicle engines are left running while the vehicle is at a standstill.

Mr. Kenneth Carlisle : Regulation 98 of the Road Vehicles (Construction and Use) Regulations 1986 (SI 1986 No. 1078) already provides that the driver of a vehicle shall, when the vehicle is stationary other than due to the necessities of traffic, stop the action of any machinery attached to or forming part of the vehicle so far as may be necessary for the prevention of noise.


UNLESS pugugly knows later different amendments.
Last edited by: Suppose on Mon 13 Dec 10 at 22:56
 Heated seats battery usage - spamcan61
>>
>> Don't think the car will use that much fuel at tickover, so I'd be inclined
>> to leave it running for most of the time, if not all of it.
>>
The trip computers on my various petrol Vauxhalls have always shown 0.2 - 0.3 gallons/hour on warm idle, so no, not a huge amount.
 Heated seats battery usage - Iffy
...The trip computers on my various petrol Vauxhalls have always shown 0.2 - 0.3 gallons/hour on warm idle, so no, not a huge amount...

Spammers,

Someone will be along in a minute to lecture us about trip computers being rubbish but....

The otherwise accurate computer on the diesel CC3 shows 0.1 or 0.2 gallons per hour at tickover, depending on how many electric toys are operating.

That's barely a pint - less than a pound's worth.

Leaving the car running is the only sensible option.

 Heated seats battery usage - legacylad
Motion carried.
 Heated seats battery usage - Crankcase
Don't forget that there is now (and has been for some years) a "stationery idling offence" that Councils can implement if they wish.

Sorry about the source, but here is a link about it from last year. Plenty of other references if you search.

www.dailymail.co.uk/news/article-1231460/Drivers-leave-engines-running-clear-screens-face-fines-idling-offence-rules.html

Cambridge does this apparently, although I've not seen a publicised case.
 Heated seats battery usage - Suppose
>> Don't forget that there is now (and has been for some years) a "stationery idling
>> offence" that Councils can implement if they wish.

See my post at Mon 13 Dec 10 22:55
 Heated seats battery usage - a900ss
Thanks all for your input

a900ss
 Heated seats battery usage - Crankcase

>> See my post at Mon 13 Dec 10 22:55
>>

Yes. Not only did I repeat your details in a different form, I even spelled stationary wrong.

Sorry.
 Heated seats battery usage - Suppose
>> Yes. Not only did I repeat your details in a different form, I even spelled
>> stationary wrong.
>>
>> Sorry.
>>

Don't start that here. I'll have you know that there is Zero tolerance* of spelling mistakes on this site.

* Zero tolerance - as decreed by Zero, spelling mistakes Rule OK.
 Heated seats battery usage - Zero
Absowlewtlea
 Heated seats battery usage - Iffy
...Absowlewtlea...

Absowlewtlea nort.
 Heated seats battery usage - Boxsterboy
Come on guys - leave the engine running to keep warm?? You bunch of softies!!

How about dressing appropriately before you go out in the morning (hat, gloves, etc.) then you won't need to leave the engine running. Thereby saving money, not annoying the neighbours, and not falling foul of eminently sensible Council rules regarding engines running in stationary cars.
Latest Forum Posts