Alternator problem?

[widster]

Hi. I've just had the battery and red engine fan light come on in the last few days. I've been reading up on relevant posts trying to find out if my alternator has stopped working or whether it's another problem? I'm wondering if it's a short or not? I disconnected the cigarette lighter a couple of days ago as it wasn't working and I'm looking to replace it. I don't think it's that but it's got me wondering .

I've changed the battery as the previous one wasn't holding it's charge. I'm wondering if the charging problem damaged it in some way? I've got a replacement battery from the scrap yard for £15 (funds are tight and a new one was several times this) which seems fine but after a few starts it's flat and I've got to connect it to my charger.

I've checked the belt and it doesn't seem to be slipping. The battery terminals also seem good and there are no obvious loose connections. Can anyone advise me of an easy way to determine whether it's my alternator or a short?

Thanks in anticipation...

[Peter Gidden]

Start by testing the voltage at the battery with the engine running. Should be 13.8-14.2 volts.

[JamesDaniel80]

A good indication should be your battery gauge in your dashboard?

Another simple way of checking whether your alternator is working is to put your headlights on and rev your engine.

Your lights should get slightly brighter when the revs go up. If they don't, your alternator isn't generating any charge.

[widster]

Thanks, I'll try those things and feed back in a bit.

[widster]

Just checked. Battery was on chRge overnight and showed 14.07 volts. After starting engine it showed 12.05 then up to 12.32 after engine switched off. Checked the headlights and they are not going any brighter. The battery's definitely not getting charged but still not sure if it's the alternator or a loose connection?

[PW@Woodsport]

Check all three pins of your alternator plug show around 12v with the ignition on and that the main charging terminal is secure.

[Peter Gidden]

Check all three pins of your alternator plug show around 12v with the ignition on and that the main charging terminal is secure.

Beat me to it!

[widster]

Thanks, I'll check tomorrow. I've picked up a spare alternator just in case too.

[widster]

Quick update, changed my alternator for a secondhand one I picked up. Took me a couple of hours but got there in the end and voila, the lights are now out so looks like I've sorted it. I did notice a spare spade connector attached to the wiring going to the alternator. It wasn't connected to anything so I left it like that. I just wonder what it's for. Would anyone know? Thanks.

[PW@Woodsport]

Just one of the many spare plugs Toyota have in their looms for something optional that was on another model.

[widster]

Thanks for that Paul. I thought it might be. It had a rubber boot around it which threw me as it looked like it had come from somewhere but all seems to be working well so I won't worry.

[stenky]

if the rubber boot looks like an odd bell, it could be intended for vacuum sensor that sends signal to "economy"-useless meter. uk cars have voltmeter there on dashboard so you don't need it

[widster]

if the rubber boot looks like an odd bell, it could be intended for vacuum sensor that sends signal to "economy"-useless meter. uk cars have voltmeter there on dashboard so you don't need it

Yes that's the one. Thanks for letting me know. You're always learning with these cars