The 75 and ZT Owners Club Forums - View Single Post

COLVERT · 8th March 2020, 12:37

I get the impression that your battery is on its last legs.--How old is it ?

If you start with your battery flat and put it on one of those chargers that light up green to tell you your battery is charged.

1/ If it takes all night before it lights up green then your battery is probably OK.

2/ If it lights up after only an hour or two your battery is on its last gasp and needs changing.

Let us know what voltage you are getting at the battery terminals with your engine ticking over.
This is an alternator output check.

Normally with a charged battery around the 14 volt mark.

Can be as low as 13.5 volts or as high as 15 volts.

Batteries like to work at around bath water temperature.

Much higher than that and you'll start to lose water from the electrolyte.---

More info in the ---really, really useful info section on the main forum page.

Look for my posts.
Colvert.

8th March 2020, 12:37	#9
COLVERT This is my second home R75 Saloon. Join Date: Feb 2009 Location: France/or Devon. Posts: 14,003 Thanks: 3,851 Thanked 2,167 Times in 1,816 Posts	I get the impression that your battery is on its last legs.--How old is it ? If you start with your battery flat and put it on one of those chargers that light up green to tell you your battery is charged. 1/ If it takes all night before it lights up green then your battery is probably OK. 2/ If it lights up after only an hour or two your battery is on its last gasp and needs changing. Let us know what voltage you are getting at the battery terminals with your engine ticking over. This is an alternator output check. Normally with a charged battery around the 14 volt mark. Can be as low as 13.5 volts or as high as 15 volts. Batteries like to work at around bath water temperature. Much higher than that and you'll start to lose water from the electrolyte.--- More info in the ---really, really useful info section on the main forum page. Look for my posts. Colvert.