Flat battery and window down?

[porterpainter]

Hi all,

I've not had much chance to play with my 2003 Tuscan since buying it, but have experienced a strange event today when going to use it.

The background - The car has been sitting for 3 weeks under a car cover at my in-laws house. I didn't put it on trickle charge as I'd not intended to leave it 3 weeks, but I only got a chance to get it today.

On removing the car cover the driver's window was down most (but not all) of the way, and the battery was completely dead. The previous owner bought a new Yuasa battery in June 2020. Window was closed when I parked it up.

I appreciate it may just have been a schoolboy error not to put it on charge, but I thought 3 weeks without charging wouldn't be a problem. Did I expect too much? Also, does the driver's window normally come down when the battery is nearly flat, or could it be indicative of something that's caused the battery to go flat?

Thankfully the window was down so I was able to get the handbrake released and move the car to somewhere I could take the wheel off to access the battery. I was then able to put a charger on it and open the boot to access the fitted Ctek charger for the car.

Once charging the hazards, the interior light and leds for the window openers were all double-flashing continuously - which I wasn't sure was normal for when the battery was just about dead? Pressing the key fob stopped this.

I didn't try to start the car, but I did attempt to open the door (in order to close the window) but the window went all the way down and then the battery seemingly died again. I've left the car on charge now, with the cover back on. I will attempt to go and start it tomorrow and see if all is well.

Any feedback about the window thing, and how long it *should* be safe to leave it without connecting the charge would be gratefully received.

Thanks
Andy

[Sagi Badger]

My experience of flat battery related to a mother in law unplugging the Accumate, anyway she hasn't done it since but the tracker on mine did drain it in about three weeks when she did. The window didn't go down, I managed to find another way to energise/enter as trying to pull the door release doesn't drop the window, anyway the question is why is your battery going flat?

There is a diode on the alternator that causes problems, I am not entirely sure what the purpose of the diode is as I have never had to investigate as I have two spare alternators so will never need one..., I find if a stock of spares is kept it will be the bit you don't have that you need. Reckon a sparky type PH'er will be along soon to shed more light on this but until then maybe sniff around and see if you have any unusual accessories.

J

[so called]

I used to leave, first my Chimaera and later a Mk1 Tuscan in Hannover Airport for two to five weeks at a time.
If I was lucky battery was OK after two weeks but three weeks was a guaranteed flat battery.
This was more or less a monthly occurrence so after about three years, the Airport Service guys started to refuse to give me a jump start.

As this was going to be an ongoing issue, the solution for me was a Battery Brain, fitted in 2007.
Never had a flat battery since and continued with that travel routine until 2017.

I did occasionally have 'funny' issues with windows and lights but not every time.
I used to ignore them as once charged and running the car seemed to reset itself and go back to normal.

Edited by so called on Thursday 29th July 13:02

[frontfloater]

Do you perhaps have an immobiliser with a tiny LED flashing light to show it's on? After I had a Clifford immobiliser fitted, I found that its LED was enough to drain the battery. Two weeks, it would start ; three weeks, flat as a pancake.

[Penelope Stopit]

Disconnect the battery and reconnect it through an ammeter, leave for half an hour with everything switched off and car locked

Check meter for value of current draw

See Find How Fast Your Car Battery Will Drain (FULL CHART)

This is good but they have guessed the current draw of components Car battery drain calculator

[porterpainter]

Thanks for all the feedback everyone, I appreciate you all taking the time to reply.

My car is pretty standard, with the only mods being shark cans and bonnet conversion - but I'll have a look around to see if anything else has been added that could be causing it. I'll also try to see if there's anything drawing from the battery when the car is off.

I like the idea of the Battery Brain - looks about the same price as a rechargeable jump starter.

Overall I'm relieved that it sounds like it could just be one of those things in respect of the battery... although the window winding itself down seems a bit odd to me.

[Basil Brush]

The light inside the boot staying on has come up a few times in the past as an issue.

I've had my battery die a few times over the years but has never caused the window to drop.

[porterpainter]

Thanks - I’ll try to check the boot light next time I’ve got a chance.

Collected the Tuscan today after a couple of days on the trickle charger, and all was fine with the car. Started just fine, window went up…so happy days.

Will keep an eye on the suggested items and do some more fettling.

Thanks again everyone

[Penelope Stopit]

porterpainter said:

Thanks - I’ll try to check the boot light next time I’ve got a chance.

Collected the Tuscan today after a couple of days on the trickle charger, and all was fine with the car. Started just fine, window went up…so happy days.

Will keep an eye on the suggested items and do some more fettling.

Thanks again everyone

And a great update this is

Proves that ECU logic falls over and window falls down with low voltage