battery not holding charge

Hi,
I've replaced my alternator as it didn't seem to be charging the battery.
I also brought a new battery. At the moment the old battery is still on. Tomorrow I'll put the new one on which will hopefully fix the problem......
The question is this.
There's 12.6v coming out the alternator is this right?
Can the battery and alternator go at the same time?
If the battery and alternator are good what else can be stopping it from charging?
The tc and abs lights come on before its about to die. When I charge the old battery it lasts about 2minutes
Thanks jon

Measured across the battery terminals with the engine running you should be getting about 14v

How old the battery they dont last forever we get roughly three and a half to four years in our conditions

I'm not sure about the old one but new one is brand new. I'm going to try it with new one just wondering if there was anything else it could be while I got the bonnet up.

It could be dozens of things - we need more details.

When did you replace the alternator? if it wasnt charging and the new one is not charging either then the problem is likely elsewhere. If there is not about 14v with the engine running then you need to look at the connections to the battery and alternator and the earth leads.
Does the battery warning light in the dashboard light up? this is an important part of the charging circuit and quite often the alternator will not work with this bulb blown.

You need to increase the engine from idle a little to check the alternator output (<13.5v)

I had this and found out that the REAR interior light had been left on by a rear passenger !!!!)

Guys, I'm sorry for been stupid it was the alternator fuse!!!

jonny2014 said:

Guys, I'm sorry for been stupid it was the alternator fuse!!!

Click to expand...

good news then !!

Excellent..........