Coming home from work last night and suddenly with a few miles to go my battery charge light came on 
I selected 20C on the aircon and sure enough the battery voltage had fallen to under 12V, so I switched everything unnecessary off and got home Ok.
After a few tests I rang Audi and ordered a new voltage regulator 'next day' before connecting up my Accumate float charger to leave on overnight.
Driving into work was unfortunately dark but LED sidelights are bright and efficient and I kept the fan and radio off yet despite the precautions, on the motorway I suddenly got a battery voltage warning symbol. 20C showed under 11V and various other lights popped up coincident with indicating to change lane. Then my speedo and tacho started dropping to zero and I thought the engine was going to die but I kept going with little opportunity to stop safely.
Off the motorway now and frustratingly stuck in slow traffic but it was still going. A few jerks at the traffic lights and at the last section I turned my lights off to save it and pulled into the back of our building put it into reverse and the reverse light killed it - so I had to push to park next to the back door.
I'd brought an extension lead and my charger but checking the specs showed it was only 1.2 Amps peak which is fine for float conditioning but wasn't going to top up a 60 AH battery enough from flat in a working day, so I wired in a lab supply set to 14V to give me an additional seven amps in current limit. 8A x 6H = 48 AH so that should do I thought.
I went to Audi by foot at lunchtime and picked up the regulator.
Coming home was equally fraught however. Frustratingly slow traffic despite not needing lights still had me dropping volts alarmingly. Thankfully I made it and pulled into my garage with the engine starting to misfire and stutter so again I only just made it.
Changing the volage regulator was tricky. The bottom screw on the alternator cover I found could only be managed by undoing the hose coupling to the thermostat housing, losing some coolant despite bungs at the ready and using a screwdriver bit with a small spanner as nothing else would fit in the space. There was an annoying cable clamp in the way too. After a bit of fiddling I got the old one off and was pleased to see the slip rings hardly worn. Chances were it was just the regulator at fault.
All back together now and sure enough the alternator charges nicely. Phew
![20161116_222652.jpg]( "20161116_222652.jpg")
I selected 20C on the aircon and sure enough the battery voltage had fallen to under 12V, so I switched everything unnecessary off and got home Ok.
After a few tests I rang Audi and ordered a new voltage regulator 'next day' before connecting up my Accumate float charger to leave on overnight.
Driving into work was unfortunately dark but LED sidelights are bright and efficient and I kept the fan and radio off yet despite the precautions, on the motorway I suddenly got a battery voltage warning symbol. 20C showed under 11V and various other lights popped up coincident with indicating to change lane. Then my speedo and tacho started dropping to zero and I thought the engine was going to die but I kept going with little opportunity to stop safely.
Off the motorway now and frustratingly stuck in slow traffic but it was still going. A few jerks at the traffic lights and at the last section I turned my lights off to save it and pulled into the back of our building put it into reverse and the reverse light killed it - so I had to push to park next to the back door.
I'd brought an extension lead and my charger but checking the specs showed it was only 1.2 Amps peak which is fine for float conditioning but wasn't going to top up a 60 AH battery enough from flat in a working day, so I wired in a lab supply set to 14V to give me an additional seven amps in current limit. 8A x 6H = 48 AH so that should do I thought.
I went to Audi by foot at lunchtime and picked up the regulator.
Coming home was equally fraught however. Frustratingly slow traffic despite not needing lights still had me dropping volts alarmingly. Thankfully I made it and pulled into my garage with the engine starting to misfire and stutter so again I only just made it.
Changing the volage regulator was tricky. The bottom screw on the alternator cover I found could only be managed by undoing the hose coupling to the thermostat housing, losing some coolant despite bungs at the ready and using a screwdriver bit with a small spanner as nothing else would fit in the space. There was an annoying cable clamp in the way too. After a bit of fiddling I got the old one off and was pleased to see the slip rings hardly worn. Chances were it was just the regulator at fault.
All back together now and sure enough the alternator charges nicely. Phew
