Alternator

Morning everyone,

Just a quick question which may have been answered many times before.

Just popped a new battery on my TD5 and left it over night.

This morning I put a multimeter on it and got 12.06 volts

Started it up and got 14.76volts but after 10 seconds the multimeter dropped to 11.47volts.
Does this mean I have a bad alternator?

Many thanks

No it sounds ok to me . You will get a spike on startup . Then it should settle down a little as the car draws power for all the electric components , did it pick up again on the metter when you rev the car .

Hi vanmancan

No increase in volts when I rev'd it or at a constant 2000 revs,
Also the battery light flickers on the dash, sorry forgot to mention,
The volts drop to 11.20 when I put my foot on the brake, no other items are on( heated seats, lights, radion etc)
Just thought that volts should be over 14 when car is running?

Are will if your batt light is coming on, then this is sounding more like the alt ,not work as it should , have you tested the alt itself for power coming out?

Ahh ok, I have googled how to check alternator but only found the way with multimeter and battery terminals, I'm not very mechanically minded, perhaps I should be

Have you download a copy of rave discovery2 maintenance manual . It's a must for any owner . It will show you how to test everything and what readings you should be getting

Chumlee said:

Ahh ok, I have googled how to check alternator but only found the way with multimeter and battery terminals, I'm not very mechanically minded, perhaps I should be

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Just use you're multimeter red on the alternators positive terminal and put your black on a good earth on the car (not the alternator) set it to 20v and test should get get a reading of 13.8 -14.2

smack alternator with a piece of wood to shift brushes down if they are stuck-do not use metal for this

IMO if the warning light comes on the alternator is on it's way out

biolandy said:

smack alternator with a piece of wood to shift brushes down if they are stuck-do not use metal for this

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Like your style

Thanks everyone,

just downloading RAVE Discovery 2 manual,

and just cant find a piece of wood big enough to smash the living daylights out of the alternator