2nd new alternator - 2nd battery charge light on

[VespaSkin]

Hi all, me again......

The issues I had previously (the rattle) was down to alternator - got one from a good autofactors - fitted and battery charge fault on dash and on MFD - took it back...

another alternator from different quality factors - battery charge fault on light and MFD

Checked with Multimeter - battery 13v when off, between 14.5 and 14.6 on tickover... The two connectors on alternator - if I put my MM probe on both - reads 2 - 3 volts (pos probe to small wire, neg to 2x large), If I put my MM on small one then negative to bonnet latch reads 12.5 - 13.5v -

am I missing something - gave the guy the reg when I purchased the alternator so assuming it's the 150amp one, what if it isn't, how much damage if I keep it on and could this be why showing battery charge fault (low amp charge kicking in warning)

Cheers all

Your stars

[VespaSkin]

Update.... all these tested at battery

No ignition - 12.8v

Ignition to on (not started engine) - 12.4 - 12.5v

Tickover - 14.5 - 14.6v

Revs (couldn't see the rev counter but about the 2k mark) - 14.5 - 14.6v

Dipped beam on - 14.5v steady

Dipped & full beam & Rear Fog & Front Fog & Stereo on (CD Player) and front cab light on - 14.3v (The battery light went out when switched lights/fogs on but came back on when I switched engine off and restarted)

Seems to be charging to me... am I being divvy or what? I don't want to put all the bits back on the car if I need to take the alternator off again

Cheers
Hope this info helps a bit

Gaz

[leehdi]

Test the battery first thing in the morning, when the car hasn't been started. That will give you a more accurate reading of the battery charge.

A under or overcharging alternator can lead to ABS and Airbag faults

[VespaSkin]

Cheers... seems to be charging though at 14+ Volts - might be lower amp alternator, will it wreck owt if it is and I leave it on?

[leehdi]

Alternator should be 13.8-14.8 volts with a max amps of 157

[leehdi]

Cheers... seems to be charging though at 14+ Volts - might be lower amp alternator, will it wreck owt if it is and I leave it on?

Lower amp alternator won't do the electrics the world of good as the alternator will be working overtime to try and power them all. So you'll burn the alternator out sooner or later, and things like lights won't be as bright as they are normally.

[VespaSkin]

Cheers again, guessing at amps to be honest as fitted it and forgot to check side of alternator - but sounds like it's charging to me, got a year gurantee so might see how it goes for a bit...

[Doggy]

It definitely sounds like your alternator is OK and the warning message / light is a false alarm.

(So long as the battery terminal voltage exceeds 2.2 V/cell or 13.2V it is charging to some degree - yours seems to comfortably exceed this & all the measurements you've noted are exactly what you'd expect of a healthy system).

It would be interesting to see what PP2000 shows - the live data will show what voltage the car 'thinks' it has......

[VespaSkin]

cheers, that's what I thought... 2 brand new with battery charge fault - nah, probably OK (Say's he tucking AA card into wallet )