New Prius battery draining while car off

Check any aftermarket components. Remote start, non-stick radio, alarm system, etc

 

Was the replacement battery fully charged BEFORE being installed ?
If no, or you don't know......do it now.

And to do anything else you will need a multi-meter.

 

What time frame: overnight, a week, longer? There's always a slight drain on a 12 battery in a modern car.

 

have you considered trading in on a newer vehicle?

 

Answer my questions first.

 

That's not good. Worth a watch:

 

Never heard of the mfd staying on after the car is off. Pretty much impossible.

Usual culprits are the back hatch is not closed properly and the side mounted hatch light is on. It has a switch On the light itself so turn it off.
People with kids seem to get there doors left cracked.

People who report 12 volt drains have one thing in common:

They do not arm the alarm every single time they get out of the car especially when it's psrked in the garage.
Thereby it will alert you a door is cracked and not allow u too arm the car.

The overhead lights get left on a lot too. The alarm does not alert u if the overheads are left on. You have to peek in the car and make sure.

There's been thousands of people on this site suspecting hidden current draw issues on there 12 volt.
Never seen one detected in the last 10 years.

Get a new battery. Keep an eye on it with a DVM. Make sure no lights are left on. I usually look at the car in the dark in the garage before retiring to see if all lights are off.

 

On the Gen 4 the MID stays on for a while after the car is turned off, but the MID turns off right away. That is the closest i have seen.

 

Talking about a G2. This is the g2 forum.

 

^ Typo in that?

 

7 Function Multimeter
(If you have a coupon, you can get one for free!)

I have 2 personal Fluke meters and some company gear, but once upon a time I was forced to go to the "Freight" and get one of these, and you know what?
They work for probably 95-percent of automotive electronics testing......and.....you cannot beat the price!
The only part that has to be "good enough" is the one that holds the leads to the components that are being tested.

What I did notice about the freebie meters is that, like Priuses, they lack a proper voltage management system.
If they're not turned off properly the battery will run down.

I think that @edthefox5 is right.
You probably will not need a meter at all because like me, your car isn't a spring chicken any more.
There could be a defective door or hatch switch that's causing your car not to shut down properly.

Keep us posted, though....
I'm a sucker for a good automotive mystery!

 

The MFD does not like to be grounded? That is strange.
Perhaps something inside it touching the chassis when it should not. If it was opened and the screws are of differing lengths, it may have a long screw where a shorter one should be.

 

Hmmmmm

I'll leave this to the G2 experts, but I'd hazzard a guess that there are some more Easter-eggs waiting for you in this vehicle's wiring.

Is the radio an OEM unit?
If not, look there or in the MDF for a wire that didn't come from the factory.
Whatever happened....JUST happened.
Meaning that unless you just now got the car, whatever is sending some of your battery juice to ground wasn't presumably doing so before very recently.

Meanwhile.....can you use some nylon (or plastic) washers or even nylon fasteners (screws) to keep the MDF mostly attached to the bulkhead while you sort this out?
I really like Prodigyplace's theory.
If somebody took the MDF apart in some ham-handed attempt at modding the car.....i.e. if your car reeeeeally doesn't have 184k, then the MDF might not have been re-assembled "correctly" and the car perhaps has hit enough Alabama pot-holes (some of them have names!) to jiggle things around.

If you're close to Huntsville, @bwilson4web LOVES it when people drop in unannounced for electrical troubleshooting!!!!
He's retired now, so he has loads of time...
AND.....probably a meter and stuff.


PS....that was satire.

 

Actually I prefer to make house calls. That way if we let the magic smoke out, I don't have "lawn art."

No, I'm still married and she has two dogs.

I collected a lot of boy's toys over the years. <GRINS>

Bob Wilson