HI, I have a 1985 Austin Mini Mayfair with a 1275 A+ series engine
I have recently had troubles with the car not starting or the battery will not hold charge,
so I set about diagnosing the problem:
Charged the battery up and unplugged/turned off everything I could whilst i went away for a few days, came back to the car not starting again (Possible drain?) so i checked the battery.
Got a new uprated battery from halfrauds as the battery was naff (didn't hold any charge for more than a days)
Thought I had solved the problem, turns out after a week of running around in the car the lights went extremely dim, and once the car was turned off it wouldn't start again
(Must be the Alternator)
So then after checking the voltages of the alternator and ensuring Earth continuity throughout the engine bay and back to the earth lead for the battery, I thought it was time for a replacement alternator!
Replaced the alternator and charged up the battery, it works fine for about a week then the radio starts cutting out, window wipers going slow etc.
So I checked this alternator and its only kicking out a maximum of 11.6 Volts (with everything on)
TIME TO GET THE HAYNES MANUAL
so I followed the wiring diagram, highlighting the circuits that apply as I went, then I checked that all the other parts of the circuits that connect into the alternator circuit work:
The battery to the solenoid
The Solenoid to the alternator
The Alternator to the clocks
Also when the ignition is off there is about 11.6V on the two large wires (brown, brown/blue) and when the ignition is on there is 11.6V on the smaller wire (brown/yellow)
Also the charging light is on when the ignition is on and goes off once started.
I've put a temporary Earth on the alternator to the car to see if there was a bad earth but there isn't
Short of sending my new A127 70amp Alternator back to minispares Im out of ideas!
but long story short the alternator wont recognise that the battery needs charging.
chris :)
