Alternator or what?

[moyesboy]

The battery dash light suddenly began staying on, on my Terrano II 2.7 TDI (02 reg).

Battery turns it and starts it OK (3-4 times now).
I've not driven it anywhere.

I checked the volts across the battery terminals and it is steady 11.8v irrespective of engine revs going or stopped.
The belt is still there and the alternator is turning.
So obviously alternator is not charging.
Anything else I should check? can it be something else other than the alternator?
or do I just buy a new alternator?

 

[rustic]

Broken wire, but unlikely.
Poor connection on rear of alternator, remove it, inspect it, reconnect it and try again.

I had a similar fault on an Austin Ambassador, I took the alternator off, and there was a spare fixing screw that had dropped into the alternator during manufacture, :doh that eventually shorted the coil to the frame.

I removed the screw, put some lacquer on the coil, and it carried on working for another 10 years... lucky or what.

So most probably an alternator fault, so it depends on how far you can test and repair it. It might be brushes, regulator or diode bank.
If there is an alternator test place locally, that can repair them for 1/3 price of a new one then that's the way to go. We have a great place in Brownhills, West Midlands.

If your battery voltage is down to 11.8 volts, then you MUST recharge it ASAP.

It is virtually flat, less than 30% charge...
best regards,

Rustic

 

[AlexD333]

The wires and terminals give lots of grief, these were the answers I was presented with when I had issues. Turned out to be battery for me, but wiring was checked. :thumb2

 

[Sweety]

Sounds as if the alternator is shot as it should be charging the battery at 14V:augie

 

[moyesboy]

Got the alternator out.
Charged the battery.
looks like i need a new or exchange alternator...

 

[macabethiel]

Rectifier ?

On mine it was the rectifier pack on the alternator it had been repaired previously and wrong amp rating was fitted by last owner.

 

[moyesboy]

Twas the alternator.
Picked up a Remanufactured one on ebay with 12 month guarantee for 90 quid delivered.
Just fitted it, no warning light, 14v when revved, 12.5 v at idle.
I'll drive it to work tomorrow.

Now, as the replacement wasn't an exchange, does the old one have any value to anyone before I chuck it?