Hi Everyone,

We have a 2007 1.8TDCi SMAX, the battery light came on while out and we continued to drive it home, things gradually stopped working enroute and then as we arrived home the engine died. Checked the voltage with a multimeter and it was at about 9.5v. 

I connected a battery charger to it for an hour and then started it check it over. The battery had about 12v at this point, I increased revs to see if the voltage increased with the alternator. It did not, I expected to see at least 14v when running but alas no difference.

I therefore suspect that either the alternator or battery is dead. However, before I make the move to buy a new battery or alternator is there any sort of fuse that can stop the alternator from charging the battery? Is there a way I can check to make sure that the alternator is actually dead?

 

Many thanks

Fred

 

 

On my brothers focus 1.8tdci we thought it was dead alternator but it turned out to be faulty pulley. On his car the pulley has a one way clutch in it which failed. So outer pulley spin at right speed but the alternator turned much slower and didn’t charge.  On 1.8tdci the pulley is not on the alternator, there is a separate shaft in between

Dredging up this old thread with an update... not as simple as others have found for me.

Rounded the top alternator bolt, therefore I had to remove the entire backing plate, wrestle it out of the car and then remove rounded bolt. Advice to all is be careful with the top bolt which has very little room.

isetta - It was indeed a faulty pulley on inspection afterwards, I had bought a replacement pulley and alternator together.

 

 

I know this comment doesn’t help you but might help others in future. Check the pulley before you waste time removing alternator. I had started removing alternator before I realised it was just pulley.  I had already moved aircon compressor out of the way which itself is not easy.