What readings should you get on a multimeter when say checking the batterys voltage first thing in the morning after being standing overnight? Also what readings should you get with the engine running?
Would using the cigar lighter with the meter for readings give the same as directly connecting the probes to the alternator or battery? As makes it a bit easier for testing, and I presume thats how these plug in car battery/alternator testers work.
Just checked the reading on my very, very old (at least 10 years) battery which still readily starts car. It's not been started for two days and indicates 12.15v at battery terminals.
as previously posted running voltage is about 14.4
most tyre/battery dealers will do a free load test on your battery, this will establish whether battery is ok, you can then check starter & connections
Depends on how cold it is etc., >12 with the headlights & the rear window demist on.
Unless you've got a faulty battery clip
It's winter...
Around 12-13.
Around 13.8.
Yep - well as near as.
Yep.
Just over 12V.
Also what readings should you get with the engine running?
About 14.5V.
It would depend on the state of the charge of the battery when you stopped the engine. And how much things like the radio memory, alarm, clock etc draws. But if starting out fully charged somewhere around 12.5 volts.
Once it's fully charged about 13.8. While on charge without a major electrical load like headlights somewhat over 14.2.
A DVM draws so little current any resistance between it and the battery shouldn't matter.
Very few alternators are that cunning, they can't tell the difference between current going to the battery & current going into loads.
If there's enough load on a non too large alternator it will pull down the maximum voltage. However, with an adequate one and everything on I'd expect to see about 13.8.
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