Skip the auto shop - Our mechanics make house calls

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?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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 draining.

Your Saturn does not have any direct relation between the door locks and the anti-theft system from the factory. If you are having issues with both of these systems in the vehicle simultaneously and the battery is draining then it...

Q: Average price to replace a 2005 scion xb 1.5L motor in CA.

Billing question sent to CS for the cost to replace an engine in a 2005 Scion xB. The engine size is L4-1.5L.

Q: Replaced clutch, transmission will not tighten against engine, need advice.

You should replace the pilot bearing anytime the clutch is replaced. You should have aligned the clutch to the pilot bearing with an alignment tool. When aligning the clutch disc you need to make sure it is centered perfectly as...

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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.