Today, i let down my S3 !!

[mikegor]

Only owned the S3 a fortnight & due to the bad weather i have not had much chance to enjoy top down stuff. The Sun was out this morning, with day off work, YES !! so i went to the petrol station for a fill up. UUURRGGHHHHH when i got back in car............. flat battery, then suddenly remembered the gent i bought the car from mentioned the alternator only starts to charge battery after 2200RPM. Fortunately garage had battery pack, so soon got underway.
Post it note required to make sure it doesnt happen again !!!!

[ukflyboy]

Sounds like you need to seriously review your driving style! ;-)

[Griffinr]

I would check its charging at the correct voltage, once the alternator has cut in it should still be charging at tick over. Cut in point is governed by the size of the bulb in the charge warning light on the dash. The higher the bulb wattage the lower the cut in speed. If the dash light fails it won't cut on at all.

[mikegor]

Yes, checked it on a volt meter, it is charging the battery at 14.2V at tick over, after i have blipped the throttle to 2200RPM !!

[Griffinr]

mikegor said:

Yes, checked it on a volt meter, it is charging the battery at 14.2V at tick over, after i have blipped the throttle to 2200RPM !!

They all do that, as they say, except mine which cuts in at 1300 since I added an extra 2.2 watt bulb in parallel with the existing one.
Well 2200 rpm at 6:30 every morning was a bit anti-social.
Rob.

[XK140]

Mike,
I felt that it was the immobiliser that was responsible for battery issues,i.e if used everyday-ish it would be fine...if not the immobiliser could run the battery down in a week or so.
One solution of course is to keep the battery on trickle charge...another could be to disconnect the battery to stop the immobiliser drain.

[mikegor]

Yes John, having tested the charging system it certainly is in top notch condition, so the immobiliser could well be an issue. I will put the battery on a battery conditioner from this weekend, also put the battery pack in the boot just in case !

[Bobhon]

mikegor said:

also put the battery pack in the boot just in case !

Hmmm, with an electrical release for the boot lid you might not be best to keep it in the boot. On my old V8S I could use the battery pack to open the boot when the main battery was flat by connecting the +ve lead to the alternator output connector and the -ve lead to a suitable earth under the bonnet.

The car didn't like being left alone for a couple of weeks at a time (I know they need to be driven).

I have my Tamora hitched up to an Accumate whenever it's parked up at home. Never had an issue with it.

Bob

[TopVpowerRoadste]

My TVR S2 (1990) has an immobilizer (a little bit of plastic you rub on a rectangular-ish piece of metal - is this genuine TVR immobilizer), I know understand why my battery is flat within a week.
How come the immobilizer runs the battery flat?
Is there an explanation for this?

Thanks,

Geoffrey

[phillpot]

TopVpowerRoadste said:

How come the immobilizer runs the battery flat?

Because it's old.

TopVpowerRoadste said:

Is there an explanation for this?

quite complicated but it's all to do with the relative passing of time.





Getting a new and modern contactless system fitted would be money well spent, imho

[TVRHasgo]

I've a Cobra immobiliser fitted to my S3 (been on it for the 17 years I've had it, you touch a widget on a contact below the steering wheel before you put key in and start the ignition) and if I don't keep my battery on trickle charge when not in use the battery is flat after a few days! So I am just in the routine of leaving it on trickle charge and there's no problem.