voltage

[AtoZ]

will an alternator running at 15 volts burn out an ECU.
ford focus.
been told the alternator needs changing because its making to much voltage (fair enough) but it has been suggested that this causes a stalling problem.
i cant see that bit but my concern is the ecu if the alternator is charging to 15 volts.

not my car btw.

 

[Stivino]

15V is ok.

 

[AtoZ]

ok.
im out of date with cars now.
my friend has had some waffle said at the garage about the cause of a stalling problem. my concern was the overvoltage of the alternator and damage to the ecu.

i used to work for volvos and they used to start on 12v but run at 9v due to a resistor.

thanks for your help.

 

[davydunt]

i find alot of cars voltage while running is around 13.6ish volt. so cant see 15v being a problem.

 

[Stivino]

i used to work for volvos and they used to start on 12v but run at 9v due to a resistor.

You're thinking of the ignition coil voltage. 12v car batteries are actually 13.2v so they need at least 15v to charge them.

 

[AtoZ]

the alternator is going to be replaced soon because of the 15v

i know alternators charge at 14.4 but this one is 15.8


you're right btw, i was thinking at the coil.

 

[KingboyD]

15.8 is too high, I would be looking at a max of 14.5V alternator output, the ECU is prob good for 20V

 

[donnymac]

15.8v is to high, should be no more than 14v to a max of 14.5v.

start to worry when you get a rotten egg smell coming of the battery,
it becomes a fire hazzard when the battery starts to cook.