My dear old Dad called me today as his 2006 2.0 petrol C-max wouldn't start. He had used it, and it wasn't turning over when he came to go out again.

I grabbed a few tools, jump leads and digi meter. Batter was reading 9V, not a good start. A jump start got it going, and there was a loud "hum" from the alternator (assumption, but was that area) when revved the voltage steadily increase to approx 10.5V and then started dropping again, down to 6V at one point. Car didn't like that at all!

So, I am guessing a new alternator is on the cards? A dead cell in teh battery was my initial thoughts before the jump start, but I don't want to get this wrong.

And on that note, how hard is an alternator on these cars? Is it a job I should swerve?

Charge the battery up first and recheck as you can't get accurate reading on charge rate with a weak/ faulty battery.

check the plug that goes to the alternator before condemning it
If its the one ime thinking of it has 3 wires to it and the wires break as they meet the plug
Had lots of focus suffer this issue

The C max do suffer with loom issues too,lad at work spent a lot of money on his

Cheers chaps!
Looks like a trip over in the morning, stick the fancy charger on the battery (a PITA to take that out too, so will just disconnect terminals) and give it a good charge for a few hours. Will then retest.

It looks like teh alternator is accessed from underneath, so will drop the tray and see how it all looks. Finding which cars are the same is not exactly easy, I think the auto's have a different alternator to the manuals. Just getting ahead of myself!

From memory drop the air con pump off and swing it down on its hoses
The alt is accessable then

Ta!
Now I remember why I like old cars....so much easier to work on.
I am really really hoping it is the battery, that is an easier fix. Though when I changed it a few years ago that started by having to remove the windscreen wipers....

If you move the covers around the front of the battery they all un clip you then slide the battery out then disconnect the cables there not that bad there's worst ones on the market to change than that ,it's more annoying that's manufactures make changing oil air fuel and pollen filters a pain !!

One other option if the c-max is anything like my focus diesel. I thought my alternator had gone and the breakdown service confirmed it. When I pulled things apart, I actually found that the alternator is driven by a vibration dampening coupling, on an extension shaft that is driven by a pulley with a centrifugal clutch and that clutch had gone.

Well, battery charged up nicely (super trick charger I was given that will charge at 25A, and is very "protective" to the battery. Cost the company who no longer needed it a fortune. Apparently.)

Seems the alternator is not charging. I can't see any extension on the alternator, though saying that I can barely see it anyway.

As TOM has a few quid, and I have no time, I have given him the number of a decent local garage, along with the price of a brand new Denso alternator (£145, recons are only a fiver less) and see where he gets with that.