10 replies to this topic

[mini_dave]

Well before i started driving i replaced the battery, and have started driving to find that the battery guage goes really down under load, so have replaced the alternator, to find it is doing to same thing again, when there is nothing using electric its a around 13 on the battery guage, but as soon as you have headlights on and the radio the battery guage drops right down to around 11 but as soon as anythink is turned off will go back up pretty quick? Does anyone no what is going on??

Cheers

[Jammy]

I'd check your earths. But I would of said it sounds like the alternator if you hadn't of said you'd replaced it. Is the belt tight enough?

[Sprocket]

Spi fuel pump, ECU, igniton, and Injector all use current when the engine is running.

Are you having trouble starting the car and with the battery going flat?

What do you mean by 11 and 13 is this + or -?

You have wired the gauge the correct wy round?

[mini_dave]

the 11 and 13 are what are showing on the guage on the dials, not sure weather ther + or -, the sender is defo the right way round, never have problems starting it, is there any chance that it might be a duff guage in the car

[Sprocket]

AH!

Volt meter, not ameter, my mistake, Doh!

Where did you connect it?

[mini_dave]

its the one thats on my dash board, im not to sure wheather it goes to the alternator or battery, if you want i could get a vid how the guage to show how low it goes, im not sure if the guage is duff tho

[Dan]

How far do you tend to drive your car? The car takes at least 20 minutes of driving to recharge the battery from a single start, if you have noticed these effects during the first 15-20 minutes of driving then there's probably nothing wrong as the battery will be eating most of the alternator output. Probably something to do with resistances in the circuit the voltmeter is fitted to. If the battery is staying charged and you aren't having any starting problems then don't worry about it.

With no electrical load, does the gauge reach 14.2 volts? That's what it should be producing.

[mini_dave]

It goes just past 13, but dont think it is going to 14.2, yeah your right it is probly within the first 20 mins, I will just leave it then and if any fualts do come about then i will investigate.

Cheers

[Sprocket]

There is also the PTC heater on cold start, that uses a shed load of current

[mini_dave]

Cheers for the advice, if i do get any problems starting it i will probly upgrade to a 70amp alternator. But as it stands its ok.

[bananaman]

I'd check your engine earth too, mine looked fine but fell apart when I grabbed it. Now I have three on various points in case it happens again. Give the battery neg cable earth connection a quick clean up too, surface rust tends to creep under it eventually.

Plus, if you leave it, the alarms can drain the batt in a couple of weeks too.

If you only do short journeys you'll find that your battery will lose it's charge, I've found that Scrappy likes to run for at least half an hour to keep the thing in shape. I rigged up a charge socket from a motorbike Optimate charger in the boot so I can plug him straight in every couple of weeks. beats the old croc clips.

Tony