Q: Q: Parasitic battery drain

asked by on

While my car is off there is a drain on the battery, I measured the drain and found it averages out at about .50 amps. I'm trying to figure out if that is high, and what the normal draw on a battery is. I have replaced the battery, alternator and serpentine belt within the last three months trying to fix this with no avail. Every time I take it to a shop to have it looked into they say it's the battery even though it's brand new. Thank you for your time. -Jhad

My car has 71000 miles.
My car has an automatic transmission.

Hi there. The Toyota standard for battery draw is 50 milliamps or 0.05amps, so you definitely have a parasitic draw. Check the obvious culprits first: the glove box light, the interior lights, a smart key still in the car, a trunk light that was left on, and so on. Then, you can start removing fuses one at a time to see if the draw disappears. After you’ve found the right fuse, start unplugging components powered by that fuse until the draw goes away. Once the source of the draw is discovered, it can be repaired or replaced as needed. I strongly suggest having a qualified technician, such as one from YourMechanic, perform an inspection of your parasitic draw so you can avoid replacing unnecessary parts.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Q: Parasitic battery drain

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Battery is drained in the morning - 2010 Mercedes-Benz C300

Hello. You have either a faulty battery (a load test on battery can easily determine status of battery), faulty charging system, and/or a substantial phantom load (parasitic power draw) that is discharging the battery while the vehicle is turned off....

Q: Determine if battery is dead

Hi. In all honesty, your best course of action is to have it charged and tested by a professional. Whether it's an old battery or there are other contributing factors, I suggest having a mechanic from YourMechanic inspect your vehicle's...

Q: I am getting a 2007 Scion tC. I am having a mix feeling about it.

Hi there. The maintenance is good on the Scion vehicles. All parts are designed to wear and tear out, but as long as the maintenance is kept up with the vehicle, then there should be minimal maintenance to perform. I...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.