I had a strange issue today which I believe has been caused by the alternator, but there is one thing that is causing me to question it. I was driving my car down the M4 this morning and slowly all the electrics were erroring one by one until the engine finally died. When recovery turned up, they were able to start the car immediately with a jump pack and proved that that there was nothing coming from the alternator as there was only 11.8v with the engine running. The thing that is confusing me, is that I would have thought the battery light would have come on to indicate low battery voltage. I have scanned all the control units in my car, and pretty much all of them had low voltage warnings on them, and only one code has stayed permanent which was on the UPC and the code was alternator type incoherence. Am I right in thinking that the alternator is dead as there is no charge getting the battery or do I need to be looking else where. Thanks for the advice in advance.
Before jumping in changing the alternator I'll get hold of the correct wiring diagram for your car and once armed with a multimeter, do some basic checks. Check the fuses on your fuse box and bell the wire from the upc to the alternator making sure it's not a broken wire or loose plug somewhere
Cheers Seb. I've taken a look at the alternator this evening and traced back the wire from the UPC to the alternator and all was good. I've taken off the regulator off the alternator and brushes were knackered, and also looks like the output shaft has completely worn though, so fingers crossed it's just a dead alternator. It been on the car for almost 140k so it's had a good life. I've attached the pics, just incase anyone can give any more input or if the alternator output shaft is meant to look like that.
