Evening folks,
Our 2004 4.4 petrol Autobiography has a drain on the battery.
Battery has been tested and is fine.
Are there any common known faults that I can look for?
Going crazy at the moment.
TIA.
 
How fast is it draining?
Is there any electrical items not working or working oddly?
Guesswork won't find it, you need to get a reliable multimeter and start measuring voltage drop across fuses, start with the higher current ones first.

Have a read at this:-

It's important to ensure the vehicle is 'asleep' before you start, latch the door locks across so the car 'thinks' they are closed, same goes for the bonnet & boot latches, then with the keys out and all access panels, glove box etc. open for access, walk away for 30 mins before you start testing - but before poking your multimeter at a fuse, have a good listen for anything clicking, whirring or otherwise functioning when it shouldn't be.
 
Morning @Earlofdon76
Check all the earth points for corrosion too.
 

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I recently had a huge battery drain and it turned out to be the auxiliary heater. I turned off the timed climate and it’s been fine since (*touch wood*). Expensive to replace, those oil burning heaters. And mine’s never worked brilliantly anyway.
 

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Good call. I don’t have one on the SC but how did you trace it or was there an obvious issue with the heater?
Tricky :cool:
Hi Tricky.
We let the car shut down and the battery was all fine. But I noticed the orange light was still flashing on the head unit way after everything should have gone to sleep. (And it wasn’t a period of time when the timed climate was scheduled to come on; the orange light blinks when the vehicle is heating up/cooling down via the aux heater).
I don’t know exactly what was causing it, but it seemed like the timed climate was constantly ‘on’ (though no fans were running). As I say, turned off the timed climate in Settings and that seemed to solve the problem immediately.
Now saving up for a new auxiliary heater (£1250+!!). Or might just go without.
Cheers,
Brasso
 
Last edited:
Hi Tricky.
We let the car shut down and the battery was all fine. But I noticed the orange light was still flashing on the head unit way after everything should have gone to sleep.
I don’t know exactly what was causing it, but it seemed like the timed climate was constantly ‘on’ (though no fans were running). As I say, turned off the timed climate in Settings and that seemed to solve the problem immediately.
Now saving up for a new auxiliary heater (£1250+!!). Or might just go without.
Cheers,
Brasso
Go without at that price, we hardly suffer arctic weather just yet. Checkout a breakers guaranteed unit from a RR specialist dismantler.
Tricky :cool:
 
Hi Tricky.
We let the car shut down and the battery was all fine. But I noticed the orange light was still flashing on the head unit way after everything should have gone to sleep. (And it wasn’t a period of time when the timed climate was scheduled to come on; the orange light blinks when the vehicle is heating up/cooling down via the aux heater).
I don’t know exactly what was causing it, but it seemed like the timed climate was constantly ‘on’ (though no fans were running). As I say, turned off the timed climate in Settings and that seemed to solve the problem immediately.
Now saving up for a new auxiliary heater (£1250+!!). Or might just go without.
Cheers,
Brassot
Surely the heater is repairable? Probably just a duff control board.
 
It could be a faulty remote start module in the rear offside that's permanently applying 12v to the FBH and stopping it shutting down.
My tiny brain didn’t realise what FBH stood for (tragic, I know) so i looked it up and came across this incredible write-up:

 
My tiny brain didn’t realise what FBH stood for (tragic, I know) so i looked it up and came across this incredible write-up:

Yes that is an excellent write up it's just a shame it's for the M47 engine so not for an L322 installation.
The L322 has a separate changeover valve to isolate the engine coolant so it can just heat the cabin.
 
How fast is it draining?
Is there any electrical items not working or working oddly?
Guesswork won't find it, you need to get a reliable multimeter and start measuring voltage drop across fuses, start with the higher current ones first.

Have a read at this:-

It's important to ensure the vehicle is 'asleep' before you start, latch the door locks across so the car 'thinks' they are closed, same goes for the bonnet & boot latches, then with the keys out and all access panels, glove box etc. open for access, walk away for 30 mins before you start testing - but before poking your multimeter at a fuse, have a good listen for anything clicking, whirring or otherwise functioning when it shouldn't be.
 
I’ve now tried just about everything with no joy.
That being said, tonight I sat inside and shut it all down.
There’s a very slight whirring coming from within the dash almost like a relay which hasn’t switched off.
Any ideas folks?
Cheers
 
I can't think of the bloody name for it... It's to do with the heating/ventilation inside the car😳
 
I’ve now tried just about everything with no joy.
That being said, tonight I sat inside and shut it all down.
There’s a very slight whirring coming from within the dash almost like a relay which hasn’t switched off.
Any ideas folks?
Cheers
Have you done any parasitic drain checks? if you have, and haven't found at least which fuse box the drain is on, then you're doing something wrong. As above, from your description it'd be an idea to check the heater blower regulator 'hedgehog' mounted on the side of the heater box on the right (UK drivers side) Disconnect it or pull the relevant fuse and then let the vehicle shutdown again to test.
 

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