How to determine the parasitic draw of a battery?
First, you will need to determine the parasitic draw of your vehicle. You can do this by performing a parasitic draw test using a multimeter and testing for current (DC Amps). To perform a parasitic draw test, you will be working directly with the car battery so it is important to follow proper safety practices to avoid harm.
What causes parasitic draw on a multimeter test?
Parasitic Draw Test with a Multimeter. On occasion, a battery may experience significant drain long after the engine has been shut off. The result can often lead to a flat, caused not by a faulty battery or through something obvious like the headlights being left on. It typically happens due to a short circuit that can be tricky to pin down.
How does the parasitic drain work on a car battery?
Once the vehicle is powered off, connect the multimeter probes in parallel to the car battery terminal and the car battery lead. This will display the parasitic drain in Amps; if the multimeter is not showing a reading then the setting on the multimeter is too high.
What does parasitic draw mean in electric cars?
Parasitic draw, also called drain, is the electric current that flows through a vehicle, both while it runs and after the ignition is turned off. You know how you can forget to turn off your headlights, and then your car won’t start the next day?
How does parasitic draw affect the battery life?
Along with being a nuisance and potentially leaving you stranded, even minimal draw can wear down a vehicle’s battery over time, often leading to performance issues and possibly a slow death. The key to good battery life is to nip any parasitic draws in the bud and also ensure the battery keeps charge above 12.4V.
When to look for a parasitic power draw?
Your battery could be near the end of its service life and it should be recycled and replaced with a new one. If the battery test shows that it is still good, then it’s time to start looking at a parasitic power draw. While you’re under the hood (or at Advance Auto Parts), test the alternator.
How to test a battery for parasitic drain?
You usually have to move the Multimeter positive lead to a separate socket on the Multimeter. Sometimes there are 2 sockets, a high range and a low range. Always test on the highest setting first. For example: high setting on your multimeter may be 10 Amp.
What should my parasitic power draw be on my car?
Power draw should be under 50 milliamps. This will display as 0.05 amps. If it’s higher, that is your parasitic power draw. Well under 50 milliamps, and you’ll need to be shopping for a battery.