[Halfman]

I bought a new battery for my 1991 214S in the summer. Since changing the alternator belt the battery doesn't seem to be holding its charge. I've checked it with a battery tester and after leaving it overnight it reads "low" (not flat) and has just enough in it to start the car. Whilst running the input charge is reading as "good", and after a short drive to work the battery reads as "charged" so I know the alternator is working. After my shift it reads "low" again.

As it's a super basic 214S there are very few electrics on the car. The radio goes off with the key, the interior lights go off properly, and the lights on buzzer works, so it's not that.

Do you guys think this is a duff (Bosch 44Ah) battery that I should get replaced under warranty? Or is there something, besides winter, that might be affecting it? Is it just coincidence that this is happening after I changed the belt, or might I have knocked or pulled something off?!

Cheers.

[Mr Teddy Bear]

What are you using to check the charge state of the battery?

Best bet is to spend £20 odd on a digital voltmeter and go from there. New battery fully charged should read 12.8 V, flat=12.2V

A new battery can be discharged down to 2/3V [ left powering an immobiliser] and still recover via an intelligent charger.

[RoverRevival]

Two common places I look are boot light and glove box light as you can’t see them on when closed.

[RoverTD]

Check that alternator is actually charging , should read 13.8 v plus after initial start.

[ROVER Cabby]

This cold snap we have had probably doesn't help either.