Problem with battery or alternator

cruizer101

I've a problem with the electrics in my car and hoping for help here. It started Thursday evening after work, battery was dead and I had to jump the car, the following morning car started fine so assumed I just left something on although didn't think I had.
That evening after work had to jump it again, also to say here I've a 60km commute on M50/M1 so car should be getting a good charge on that run twice a day. On way home firstly when I switched lights on it seemed like car cut itself out but started again straight away as i was moving anyway.

Then on M50 sitting stopped in traffic, car completly died, tried starting but no power at all. So i got out called recovery, in meantime guards came along and pushed car to hard shoulder, I jumped in to just grab my coat and tried to strart just to see and sure enough it started. I wasn't taking chance so got recovered to just off M50.

Got a lift home and went back next morning to get car, sure enough it starts, after getting it recovered to home no power again. Jumped it at home to get it started and measured some voltages battery 12.4 so bit low, alternator was giving just over 14 with heater fan and light so seems ok, anyone
any ideas or suggestions how I can tie down where problem is. Thanks

visual

It appears to be the battery
Get the battery tested most places that sell batterys can test battery before replacing it.

cruizer101

Problem is they are all closed over the bank holiday weekend an ideally I need it grand for tuesday morning, or at least know whats wrong with it.

I've been looking at it some more the battery is giving a voltage of 12.58 which is just of the recommended 12.6 and the alternator is giving just over 14 when I'm fully loading it (fan, window heater, lights and radio)
So both of them appear to be working ok.

I went to clean the terminals on battery anyway as there was some blue deposits on the positive terminal, i noticed the negative terminal was also a bit loose. So this kinda makes me think it may have been a loose connection.

The fact that the voltages are alright and when the car died it did it straight away no lights dimming kind of thing, like was switched off.
And maybe the times it was jumped by clamping the terminals it remade the connection.

I can't seem to tie down where the problem occured anyway.

Esel

cruizer101 wrote: »

I went to clean the terminals on battery anyway as there was some blue deposits on the positive terminal, i noticed the negative terminal was also a bit loose. So this kinda makes me think it may have been a loose connection.

A good clean with a fine wire brush would be a good idea.

Be careful if blowing the blue/white residue away, because it is corrosive and therefore harmful.

A light smearing of Vaseline is a good idea before you fit and tighten the clamps.

If problem is still present and a bad battery is not the cause, check the earth strap for integrity and a good connection to the chassis.

Xantia

Yes definitely a loose connection at the battery terminals when you see those deposits.
As previous poster - clean, vaseline and tighten.
You can change the terminals - I use This Type