alternator fuse / relay

[mike_s14]

having had a new battery and alternator the battery still is not charging... checked the metal fuse above the battery and thats ok

so what other things can I check? is there a relay on this circuit

 

[Muttley]

How old is the battery - it may be worn out and not holding charge.

Otherwise it could be the voltage regulator, which is on the alternator itself.

Or, If you're very lucky, it might just be the brushes on the alternator. If they're less than 5cm long, time to replace them.

 

[mike_s14]

battery is less than a week old, and alternator and belt was put on today

battery light still on the dash and today got to the mot station and wouldnt go any further, will have to go out soon with a charged up battery and get it back

could it be the wiring, how do I check

 

[mike_s14]

anyone?

 

[Muttley]

Simple checks with a multimeter at the battery (with someone else to rev the engine) will give you a clue.

http://www.carbasics.co.uk/How_to_test_your_alternator.htm
http://www3.telus.net/chemelec/Projects/Alternator/Alternator.htm

 

[DPJ]

Fault with alternator control circuitry?

Bad engine earth (unlikely)