When battery drain when engine is off

@christiana75331 sounds like you are dealing with a parasitic battery drain. That is where the battery drains the battery quickly even during short park periods with everything turned off. It indicates that a module or circuit is remaining active when the ignition is switched off.

A few checks you should before testing for a parasitic drain. Unplug and aftermarket GPS etc, disconnect any USB chargers, dash cams, OBD-II scanners, or Bluetooth adapters. Next touch the Alternator. After your car has been parked and has complety cooled down, touch the alternator casing. If it feels warm to the touch, a bad alternator diode could be draining your battery. Check the trunk next. Lower the rear seats at night to verify the trunk light shuts off completely when the trunk is closed.

Here are the steps to follow to find a parasitic drain:

Ensure the battery is fully charged before starting.

Turn off all accessories, interior lights, HVAC controls, and the ignition.

Pop the hood and open the driver's door.

Trip the door latch:

Use a screwdriver shaft to push the driver's door latch mechanism into the locked position. This fools the car into sensing the door is shut so interior lights power down. Lock the vehicle using the key or fob. Wait 15 to 20 minutes for all CAN-bus modules to enter full sleep mode. Keep key fobs at least 15 feet away during testing.

Now you are ready to measure the current draw:

Set a digital multimeter dial to 10A DC and insert the red probe into the high-current 10A jack.

Unbolt and remove the Negative (-) battery cable from the battery terminal post.

Place one meter probe on the negative battery post and the second probe on the disconnected negative cable clamp to bridge the circuit in series.

Then read the current on your meter. A normal power draw will be around 0.02A to 0.05A (20mA–50mA) used for keyless memory and clock retention.

A parasitic drain will be anything over 0.08A (80mA). Rapid battery drain usually registers between 0.30A and 2.0A+.

Now you will need to isolate the circuits to determine where the parasitic draw originates from. This can be tedious so consider having someone help you with this by monitoring your multimeter readings. Your Vit should have tow fuse boxes. There should be the

a. Under-hood fuse box (adjacent to the battery) and the

b. under-dash junction block (driver's footwell area).

Use a fuse puller (pliers) and remove one fuse at the time. Each time you pull a fuse, check the reading on the multimeter. If the current draw remains high, reinstall the fuse and move to the next. If the current drops sharply down below 0.05A (50mA), you have identified the faulty circuit. Now you would need to check what is on that particular circuit. Could be a shortened circuit, corroded cable or failed device. Let us know what you find out so we can try and help you further if needed.

Essentially you want to do what is shown in videos like this