Everyone I have ever measured, (and that must be in the hundreds) will show a a slightly lower battery voltage at idle than at higher RPM. If the system is loaded with e.g. lights/heated screen etc. that the difference between becomes that much larger.
Car electrical experts required...
- Thread starter lordrobs
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Everyone I have ever measured, (and that must be in the hundreds) will show a a slightly lower battery voltage at idle than at higher RPM. If the system is loaded with e.g. lights/heated screen etc. that the difference between becomes that much larger.
14.4 if we are being pedantic, although it will vary a little with temperature, higher when cold, lower when hot.
Soldato
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Before you replace the battery, check it isn't the sort that needs topping up with deionised water every so often.
My car was refusing to start if the previous trip was less then a few miles, I've just topped the battery up and it now seems fine (after charging it by starting it with jump leads then driving it a bit). I've still parked it where I know I can bump start it just in case.
My car was refusing to start if the previous trip was less then a few miles, I've just topped the battery up and it now seems fine (after charging it by starting it with jump leads then driving it a bit). I've still parked it where I know I can bump start it just in case.
Soldato
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Thanks for the info.
Soldato
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alternator spins slower when idle... I wouldn't worry about it
Indeed it does, but as has been said numerous times over, dimming lights and slow wipers are not normal but should be a simple fix.
