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Discussion Starter · #1 ·
I went for a walk yesterday near Castleton in the Peak district and left the TT parked very close to a fence, so got out of the passenger side.

I didn't realise that the buzzer doesn't sound, if you leave your lights on, when you open the passenger door :roll: . That's my excuse anyway!

Consequently after 6 hours I was a little worried to see my tail lights on when returning :eek:

The starter wouldn't even go click and just extinguished the dash lights instead. Luckily we were on a hill and pointing downhill. After a push we got rolling, but the usual clutch blip in 1st to bump the engine didn't start it because the battery was so flat! I had to put it in second (1st just stalled the car) and let the alternator do some generating, for a few seconds at reasonable revs, to provide enough current to get the electronics working. Then engine power came back on line!

Luckily we were on a steep and long enough incline to do this. No ill effects apart from having the radio go into safe mode.

With only sidelights drawing perhaps 40W the 60AH battery should have been capable of withstanding the discharge but it's old and probably not 60AH anymore and the car had been garaged for a while without much use so wasn't in the best state of charge.

I'll be more careful next time :roll:
 

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Luck you were on a hill John :)

Time for a trickle charger then ?

Mark
 

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John-H said:
I didn't realise that the buzzer doesn't sound, if you leave your lights on, when you open the passenger door :roll: :
I didnt know that either. I might find this useful one day =)
 

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John-H said:
I had to put it in second (1st just stalled the car) and let the alternator do some generating, for a few seconds at reasonable revs, to provide enough current to get the electronics working. Then engine power came back on line!

Luckily we were on a steep and long enough incline to do this.
It's not called 'Hope Valley' for nothing :!: :p
 

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:eek: John I' dissapointed in you :) fancy not using your accumate :eek:
Im curious John how didnt you hear the buzzer ? or did you get out of the passenger door ? so who was driving ?? :? if you got out of the passenger door did the driver not hear the buzzer :?
Anyway lucky you got it going :)
My back is still bad :( so I spent all day getting pampered :p which reminds me , I must remember to to get the cape on my batman outfit trimmed to stop me tripping over it :eek:
 

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Is it safe to bump start a 4 wheel drive car? I thought this was no no because of the dif or something. Perhaps this doesn't apply because the Haldex isn't 4wd all the time???? Maybe I'm just misremembering something.
 

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While we are on the subject flat batters.
My Dad's 5L V8 lump has gone flat a few times lately and I have used the TT as the donor car when jumping. I always jump correctly by connecting the leads to my car first and then the +ve to the +ve connecting site on the V8 and finally the -ve to the V8 chassis (all with my engine off). This usually gets the car going (just about as the V8 uses a 90 Amp battery).

Yesterday my Dad did it by himself and just connected my battery to his with my alternator running. As his 90 A battery (which is approx twice the size of ours) was flat as a pancake I am concerned that my alternator may now be fecked.
Anyone have any thoughts on the subject? :cry:
 

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Discussion Starter · #8 ·
gt russell said:
:eek: John I' dissapointed in you :) fancy not using your accumate :eek:
Im curious John how didnt you hear the buzzer ? or did you get out of the passenger door ? so who was driving ?? :? if you got out of the passenger door did the driver not hear the buzzer :?
Anyway lucky you got it going :)
My back is still bad :( so I spent all day getting pampered :p which reminds me , I must remember to to get the cape on my batman outfit trimmed to stop me tripping over it :eek:
I was aware the battery was down to 40% as I measured te voltage when I was doing some tests but I had hoped the recent drives would recover it :roll: .

I did scramble out of the passenger side becaust the driver's door was up against a fence and as I discovered - YES - the passenger door doesn't sound the buzzer :eek: :!:

It's the leaping off the wardrobe in the bat cape that does it Russell :wink:

Lock_Stock said:
Is it safe to bump start a 4 wheel drive car? I thought this was no no because of the dif or something. Perhaps this doesn't apply because the Haldex isn't 4wd all the time???? Maybe I'm just misremembering something.
It works and it's OK. With the Haldex you can even tow the car with two wheels off the ground it's very tolerant of things like that.

You might be thinking of the warnings against tow starting cars with catalytic converters - there's a danger unburnt fuel will get into the cat and burn there causeing it to overheat and melt. Even this is a bit of an over-reaction - it's only where, say your coil packs have failed but your injectors are still pumping fuel into the engine. That's not the case with a simple flat battery where everything is otherwise working fine. Bump startingt will just turn the engine over like the starter does until it fires up.
 

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Discussion Starter · #9 ·
acmurray said:
While we are on the subject flat batters.
My Dad's 5L V8 lump has gone flat a few times lately and I have used the TT as the donor car when jumping. I always jump correctly by connecting the leads to my car first and then the +ve to the +ve connecting site on the V8 and finally the -ve to the V8 chassis (all with my engine off). This usually gets the car going (just about as the V8 uses a 90 Amp battery).

Yesterday my Dad did it by himself and just connected my battery to his with my alternator running. As his 90 A battery (which is approx twice the size of ours) was flat as a pancake I am concerned that my alternator may now be fecked.
Anyone have any thoughts on the subject? :cry:
I'd think you're probably OK - it will suddenly drop your battery voltage as he connected the flat battery. That way the alternator will suddenly start to work hard but most of the sudden surge of current will be from your battery to your Dad's battery - your battery will smooth out the shock to your alternator.

Worst would be, if having got your alternator churning away flat out into your Dad's flat battery, you suddenly disconnected the jump leads. All of a sudden the load will be taken off your alternator and it's output voltage will tend to instantly surge upwards - this is where the electronics can get fried if it's not been designed robustly enough, although your battery will tend to clamp it and the alternator should have a surge arresting circuit in the regulator. Best to have a few electrical loads on, like lights to act as a damper too, to be on the safe side.
 

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John-H said:
acmurray said:
While we are on the subject flat batters.
My Dad's 5L V8 lump has gone flat a few times lately and I have used the TT as the donor car when jumping. I always jump correctly by connecting the leads to my car first and then the +ve to the +ve connecting site on the V8 and finally the -ve to the V8 chassis (all with my engine off). This usually gets the car going (just about as the V8 uses a 90 Amp battery).

Yesterday my Dad did it by himself and just connected my battery to his with my alternator running. As his 90 A battery (which is approx twice the size of ours) was flat as a pancake I am concerned that my alternator may now be fecked.
Anyone have any thoughts on the subject? :cry:
I'd think you're probably OK - it will suddenly drop your battery voltage as he connected the flat battery. That way the alternator will suddenly start to work hard but most of the sudden surge of current will be from your battery to your Dad's battery - your battery will smooth out the shock to your alternator.

Worst would be, if having got your alternator churning away flat out into your Dad's flat battery, you suddenly disconnected the jump leads. All of a sudden the load will be taken off your alternator and it's output voltage will tend to instantly surge upwards - this is where the electronics can get fried if it's not been designed robustly enough, although your battery will tend to clamp it and the alternator should have a surge arresting circuit in the regulator. Best to have a few electrical loads on, like lights to act as a damper too, to be on the safe side.
Thanks John. :)
 

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Yes John it missing the bed from the wardrobe that did it :( Im sure I saw bat man fly with his I just cant get mine to work :cry: :lol:
 
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