Skip the auto shop - Our mechanics make house calls

Q: Parasitic current draw with ignition off

asked by on

Parasitic current draw with ignition off kills battery when not started for a couple of days.

My car has 160000 miles.
My car has an automatic transmission.

A: Hi. The first thing to do is to look in the...

Hi. The first thing to do is to look in the vehicle when the doors are locked to see if any lights are staying on. Do not overlook the hood light and map lights. The most common failure to cause the draw, since it only takes a couple of days, is the alternator shorting internally in the voltage regulator. If no lights are on, then the alternator will need to be inspected for possible electrical problems. If you need further assistance, I recommend you have a certified technician, like one from YourMechanic, replace the alternator if it is diagnosed to be the problem.

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: Windows won't close

Looking at the wiring diagram for your vehicle, I don't see any part of the circuit that would affect both rear windows, without also affecting the front. Because of this, my guess is that you have two failed power window...

Q: Clicking sound from tire

Hi! The sound you are describing is a common giveaway of a faulty CV axle. I suspect that the joint inside of the axle is binding up and is causing the noise. The joints on your particular vehicle may fail...

Q: Car misfires while idling

If you think your car is misfiring, you should have a Check Engine light up on the dash. If you have a Check Engine light, start by having the vehicle scanned for trouble codes. If any cylinder is misfiring, the...

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...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...