on my hyndai azera 2007, when we jumped the car, it showed a constant 14.8 v. and upon turn off battery showed 12.5v. a few hours later it showed 10.3v so i assumed a parasitic draw. when using the multimeter on 10A (DC) it reads 0, when a connection is made through the meter and negative terminal/ battery ,when i switch it to milliamps it reads .10mA. which seems way too low. tried opening the door and switching to regular amps and still nothing, again in miliamps it shows .10mA (DC). I'm not sure what is happening. any ideas? I've watched video and read tutorials on how to do the test and everything seems to be right but the multimeter only shows .10 when set to the max of 400mA and 0 when set to max 10amps.
FYI : Just purchased this multimeter today since I couldn't find the old one.

Any ideas?


Thanks
-victor.

 

First, the battery will show higher volts when the engine is running because the alternator is charging the battery. It's normal to be 13+ volts When you shut the car off it should drop to 12v because that's all the batter can put out. If the voltage drops to 10+ volts and there is no draw then the battery is probably bad. Have it tested.

 

14.8v while running is the alternator voltage charging the battery and providing electrical energy for the accessories. 12.5v is right on for engine off voltage. At first, it does appear to be a bad battery or parasitic draw. The multimeter is easy to use for voltage. Just measure across the part you want to test. However, the ammeter is different. The 10Amps is a different connection on the meter. Please check to see if you are using the meter properly. Inserting the multimeter between battery ground and the wire for the car ground should display any such parasitic draw (usually anything over 50mA). If it is a bad battery then you should be able to go to an auto parts store and have them test it (some do it for free).

 

I had a similar problem, battery voltage dropping and car dying overnite.
Measured parasitic draw using the ampmeter-in-series-with-negative-terminal
methode, 6 millamp drain, which is OK.

Dealer keeps looking for a drain, while repeatedly asserting that the battery is fine. Finally, after looking at the car for a week, they tell me I am imagining the issue, and all is well.

At my insistence they do a final battery test, and conclude its a bad battery, and replace it. Problem solved.

The test alleges overly high internal battery resistance. This usually indicates sulphur deposits. Grumble.. amateaur hour...

 

Turn your head light switch from auto to off.