Hi,
I have an 07 plate IS220d and just before Christmas the battery died and had to be replaced. Since it has been replaced it has been a little sluggish to start, especially as the car is not used for long runs very often.
Last week the battery 'died' and I had to get the AA out to take a look. First thing he did was check the power, it's a 700amp rated battery and had high 500s in at at the time. This was insufficient power to start the engine at all. He boosted it and got it running, did the usual checks and declared that it wasn't draining power when idle, was a good battery and the alternator works fine. We left it running for 10mins (614amp charge) and tried to start on its own which it did, albeit only just. He then tested the starter motor and found it was needing high 500s, just into 600amp current to start the motor.
I've contacted the company who sold and fitted the battery - they say it is the only battery on the system for the car and should be fine. Phoned round a few other large garages and they all recommended stronger batteries when I just asked for a battery quote - Kwikfit 770amp, Halfords 830amp, local garage 730amp.
So here's the problem - the cars dead again. Do I get a new battery with a higher rating, or do I get the starter motor looked at (AA guy reckoned it shouldn't need that much power and should be nearer 400 to start). I obviously don't want to do the wrong choice then pay for the other one too so any advice is very much gratefully received.
Thanks
