ey guys got myself a multimeter to test my alternator and battery got a few questions though as im not sure what the voltage is suppost to be on both alternator and battery. So what setting should the multimeter be on? How do I test the alternator for voltage? And what volts should be going through the battery and alternator? Cheers for any advice
put your multimeter on volts u only need volts with one decimal place eg 12.5 volts your battery should be around the 12 volt mark normal when car is running should be around 13 - 14 volts anything less than 13 and your car isnt charging
put your multimeter on 20 DC volts, DC is the symbol with a line with dots underneath and AC is like this ~
A fully charged car battery should read ~12.6V across the terminals with the car off. With the car running, the voltage across the battery terminals should read ~13.8V at idle and rise to ~14.0-14.2V (and no greater) if the throttle is opened a little. It should stay at that level if you switch on some of the electrical load like headlights and fan. If you put the red voltmeter lead on the bolt on the back of the alternator with the thickest wire attached to it and leave the black wire on the battery earth terminal, you should get very close to the same reading as you do directly across the battery terminals.
you can test your alternator by starting the car, turn the hi beams on then pull the positive terminal off the battery, if it keeps running you have a good alternator
