It will be fine, that charger doesn't go over 12v so no different to having a charged battery in the car, the alternator is a battery charger and that can run up to ~14v
If you are worried just disconnect the negative terminal of the battery.
If it didn't go over 12V it wouldn't charge the battery.
I thought it would be easy to evidence my stance but there seems lots of questionable advice on the web about charging in situ. Maybe things have changed but unless you can get a guarantee from someone who really knows, I wouldn't do it.
@car-man?
Does the owner of the charger not have a user manual for it?
Nah, it's years old.... I think my dad forgot he even had it... https://cdn.jsdelivr.net/gh/joypixels/[email protected]/png/64/1f601.png
I've charged loads of car batteries in my time in-situ. Whether it is right or not, is another matter.
But, as long as the ignition/radio etc. is off, and if the battery has removable plugs, then loosen them - you should be fine.
However, I take no responsibility, given RBZ's warning, for any bodily injury, fire, damage etc. caused by your actions!data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7
Ok, started the car today, fired up pretty quick and first time.
Thought I would test the battery with a different multi meter, still reading zero.
Now I know they are set right so why can't I get a reading, no am placing them on the positive and negative on the top of the battery, so what am I doing wrong?
As suggested previously, try a disposable battery.
Pic of the second meter?
Take the car for a long run, at least an hour on a road at 50mph. Leave the radi, aircon, headlights etc off. Bring it home and garage overnight. Make sure everything is switched off. This includes alarm system and its internal motion and door sensors.
See if it starts ok next day and ensure that the car gets a reasonable run at least weekly
Go easy on air con/heater/radio
If this doesn't solve problem get check at auto-electrician. Battery/alternator/wiring/short circuit in wiring
That is set to measure capacitance. The dial should be here:
https://www.avforums.com/data/attachments/1132/1132637-75dca69c6f8407dfdb7a8eddd9c21fb7.jpg
And put the red lead into the right hand red socket marked VĪ©ABlack one in the middle socket marked COM.