Car is Dead!

Try a different door or use the key from your fob to gain entry then see if it will go into Ready Mode? You may have inadvertently left a light or something on all weekend and drained the 12 V accessory battery. The cold weather probably is not helping either. If you can get the hatch open and have a voltmeter check the 12 V battery.

 

Since you have a multimeter, check the Fob battery, it must read stated voltage or higher, try the other Fob that you should have gotten with the car. Yes, a multimeter can read 12VDC with no problem. Or any other voltage. To read current the meter must be in series, and current read selection. If you jumper the battery, make sure that you let the car run for a long time (8hrs) for a good charge. Naturallly after obtaining READY remove jumper cables!

 

You want to measure voltage, not current, so the amperage rating of the meter is not relevant.

By 'dead', do you mean that there is no sign of life in the car? Will the interior lights turn on? If you press the Power button, will part of the dashboard light up and tell you that the key is not detected? If nothing lights up, you have a problem with the 12V system.

Don't try to read amps on a bare battery! This serves no useful function. On the fob battery, is just helps drain the battery really fast. On the car's 12V battery, this action will blow up something, hopefully just a protective fuse in the meter. In the absence of such a fuse, something will get really, really hot, possibly with sparks or smoke or molten plastic or metal.

 

If you cannot even get a dome light or map light on, or see a red light in the lower right corner of the dashboard display (solid red for door open, flashing red for immobilizer that always flashes when the car is off and unattended) the 12V is somehow dead.

At this point the key fob battery is not relevant.

 

Just to be completely clear: you set your voltmeter to "volts", touch the meter leads to the battery terminals, and it reads zero volts?

 

Either you have a 12V battery that very suddenly went very bad (0 volts?) Or you left something turned on without realizing it that drained the 12V battery. I know you have said twice now

But perhaps you just didn't realize something was left on. You either need to replace the 12V battery in the vehicle, or you need to jump start it and let it charge back up.

 

I'm NOT saying the OP did leave lights on, or hatch or door open, or something that could drain the battery down. Because obviously, objectively from the internet how can I know?

But I always thinks it's funny when a poster will say, I did NOT leave lights on...or I did not leave a hatch open....

It's an accident. So if you did? You wouldn't necessarily know. It's like being a sentry and saying "I know nobody sneaked past me". Because if they sneaked past you...you wouldn't know...

In a way? Doesn't matter. First step is figuring out what has happened, then you can find out why....

Just get the status of your 12vlt confirmed.

 

The last few dead batteries I have seen did not read 0 volts. Perhaps your 12v battery is really toast and jumping wont save it.

I would take it out of the car and have it charged and tested. But it sounds like you will need a new 12v battery anyway.

MB860 ?

 

+1, I would say it is impossible for a disconnected flat battery to read zero volts unless it has an internal open circuit fault.
If it is a short/leaking circuit on the car, disconnecting the battery should result in the voltage rising as the load is taken off.

 

To the OP: is your voltmeter digital? An anologue meter will do to see what zone your battery's in, but a fairly accurate digital voltmeter is needed to to zero-in on it's state. Anything but a bargain basement meter should be ok.

And it does seem odd to be reading zero. Even an ill battery should read something. FWIW, you can read the voltage at the jumpstart terminal in the under-hood fuse box: positive (red) lead to the terminal, negative to something like a bolt on the engine.

 

Were you able to get the hatch open without power and check voltage directly at the 12VDC accessory battery? Where is the charge plate? Are you referring to the jump points under the hood?

You can jump the car from the front or the back. Front the under the hood jump points, Back at the 12VDC battery directly. Be careful of polarity either way.

IDK but one of the smarter members following this thread might, are the jump points under the hood always live, meaning with the car off is there any voltage? Would they only be live to give a jump when the car is in Ready Mode, but able to receive a jump with the car off?

 

I'm not sure how you can check the overhead map lights after the 12V has died. Mine would look and feel identical in the On and Off states.

 

How are you checking the 12V battery voltage? Are you checking the 12V battery directly or are you checking it by the fuse box under the hood?

From your post... I have a feeling that you may not be using the voltmeter properly. You don't have to disconnect the battery terminals to check the voltage. I think getting someone else with mechanical knowledge to look at it is your best bet.

Oh...VERY IMPORTANT: THEY NEED TO FOLLOW THE CHARGING INSTRUCTIONS IN YOUR OWNERS MANUAL OTHERWISE THEY COULD DAMAGE YOUR ELECTRICAL SYSTEM!!!!!