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Discussion Starter #1
Just tried to use my NG900 and the battery is COMPLETELY dead - no ignition lights, remote entry, nothing.

Tried to jump it, first with a Clio (which didn't work, I figured the car wasn't man enough!) and then my brother's BMW but all I got was a small whirr as it tried to turn over, then the clicking...

Can a battery seriously have gone this flat in two days? I'm pretty sure I didn't leave anything on - I'm a little bothered by the fact that it won't even jump...

Battery is now on charge - what are my chances?

Cheers guys!
 

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The battery service includes the following :
the load test
The alternator output test
The inspection of the cables and connections
even a starter test (measure the draw in amps), usually not necessary.
The battery fluid level should be checked as well.
To do all this just takes less than $100 in equipment (thanx to HF) and some training (courtesy of VW general repair).. of course , I have forgotten everything.:cheesy: ...
BTW, if the battery now "sucks up" the charge with copious amp readings, then, quite possibly the alternator is at fault. ... or the cable.
 

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Discussion Starter #3
Hmm, bit involved for the minute - I'm pretty sure the car is ok, but the battery is a cheap one anyway by the look of it.

Is currently on charge and I'll stick a mulimeter on it.

Have been eyeing up the Optima Redtop range of batteries - anyone got any experience with them?
 

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it shouldnt matter how dead hte battery is if you're jumping it with a good battery the car should start right up and run

try a couple different spots for the ground, on my c900, i always had to use the hood hinge thing, even when I clipped it to the engine block it didnt work
 

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Discussion Starter #5
Nah, I went straight from terminal to terminal, i'll take the risk of an exploding battery! :cheesy:
 

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A really dead battery will load the good battery in the car used to provide the jump start, often just enough so the starter solenoid clicks, and the starter does not crank. If you run the other engine for about 15 minutes (longer in below freezing weather) b/f attempting to start the car, it will charge the dead battery enough to avoid that problem.

Even a cheap battery will not go dead in two days, unless outside temps are very, VERY low (like, -20). However, if the battery is not being charged enough while driving, and if it is almost discharged when the engine is turned off, letting it sit for a day can do the rest.

After installing the charged batery back in the car, it may be a good idea to measure the battery voltage with engine running as well as engine off. With engine running, lights, radio, ACC on, the voltage supplied by a good alternator, and measured at the battery terminals should be 14-14.5. With engine AND ignition off, the battery should maintain 12.6V give or take a bit.

With ignition on, and engine OFF, 12+/-0.5V, depending on what acessories are on at the time (headlights, radio, ACC fan all add to the battery load.
 

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Discussion Starter #7
Well its still on charge but I'm not holding out too much hope... I've ordered an Optima Red Top battery for £90 so it doesn't matter if it doesn't charge - if it does it can go in my C900! :cheesy:
 

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StormCrow said:
...it doesn't matter if it doesn't charge - if it does it can go in my C900! :cheesy:
my kind of logic, you can never have enough spare batteries, LOL!
 

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Discussion Starter #9
Well it charged...

Plugged the battery back in this morning - the car starts but runs REALLY badly - I'm hoping its just where it's relearning it's settings. Haven't had a chance to drive it yet, so I will do that and it should be ok...
 

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StormCrow said:
...- I'm hoping its just where it's relearning it's settings. Haven't had a chance to drive it yet...
(!?) AFAIK, re-adaptation only applies to controlling the turbo under acceleration, not to an idling engine!

Can you measure the voltage at the battery terminals with the engine (and presumably alternator) running?
 
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