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Discussion Starter #1
I have a problem thats intermittent I lock the car return the next morning unlock the car with the remote try to start it and just get the clicking and flashing lights hook up to a spare battery and it starts on the button drive 2 miles to work and park up when i return after work it starts no problem. the battery is less than a year old this has now happened 3 times in the last 4 months when the engines running the battery shows around 13.5/14v with the engine off it shows 11.75 ish the car seems to go to sleep ok ie the P light on the autoshift is off can anyone shed any light on the problem?
 

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sounds like a dodgy battery to me, a fully charged battery should show 12.7v or very close to. yours is no where near where it should be. might be worth charging it with a good charger if you have one.
 

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You might be using all the power in the batt on your short journeys that the alternator cant replace in time.

It is colder of a night which takes its toll on a low charged batt.
 

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Discussion Starter #4
its been ok on the few days we've had a frost but has failed on not so cold nights its a good quality bosch battery and if it was due to the low mileage I do to work surely it would happen more often
 

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11.75volts in a battery is somewhere around 25% charged, a very flat battery. 12.6 is about 90% charged. i would give it a top up on a good charger (dont rely on the car doing it) then leave it for a while to settle and then recheck the voltage. a drop tester would also help to see how good the battery is. it could be a faulty one.
 

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Discussion Starter #6
ok dont know if this will help anyone to diagnose my problem today i was in a queue to get the car washed the heater was set to auto and i noticed the fan speed go up and down a few times i have not noticed this before is it supposed to do this?
 

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Discussion Starter #7
11.75volts in a battery is somewhere around 25% charged, a very flat battery. 12.6 is about 90% charged. i would give it a top up on a good charger (dont rely on the car doing it) then leave it for a while to settle and then recheck the voltage. a drop tester would also help to see how good the battery is. it could be a faulty one.
ok thanks i will try this
 
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