Jacked a c63

9V should have some power to the car to start all the lights (according to auto zone)

I had it charged and jumped to 12.5V but then the car still wouldn't start

chrisridebike8

No, the car is smart. If there is not enough voltage the car basically says "no way. voltage is too low. I'm not even going to bother doing anything." Even my Ryobi power tools do that. once the battery is at a min voltage, the tool shuts off. You should try a brand new battery. having to get the battery charged up sounds like the battery is bad.

Jasonoff

This math is not adding up man.

A fully charged battery diagnosed as "fine" virtually unused drained down to 9V in less than a week is not "fine" by any means.

You have some crazy parasitic draw somewhere if that battery is actually "fine".

Crya

iTrader: (1)

This seems pretty silly that this has gone on this long. K.I.S.S. It's the battery.
1. Remove current inoperable battery.
2. Install known working battery which can crank over another vehicle.
3. Fire it (the AMG) up.
4. Buy new battery as you've now proven the other "new" battery is "bad".

Jacked a c63

I had it towed to the dealership,

Towing was a pain, the car wouldn't shift into neutral at all.

I don't know how they ended up towing but eventually they got the car in neutral but the steering locked up with the wheels turned to left. So they couldn't even push it straight!

The dealership put a new battery in, it got some power but eventually died again. They said its a wiring issue from the battery going to the front.

They found the issue and fixed it but now the car starts and misfires with rough idles!!!!

Jacked a c63

They found a wiring issue from the battery going to the front of the car, they fixed it and gave me a new battery. They said something about a module draining the car battery when left sitting. but i've left my c63 sitting for 4-5 months in the winter before without ever starting it up and never had an issue and it was from my stock battery from 2009-2018. My stock battery lasted 9 years until May of this year.

This time i left it for a 2-3 weeks and it dies.. which makes no sense especially when the battery is new.

But now the car is having misfires and rough idles!

Jacked a c63

We all thought it was the battery but turns out it was a wiring issue and a module that was draining power.

Crya

iTrader: (1)

Damn man, sorry to hear about these issues. Friggin electrical gremlins are the worst! Good luck and hope you get it sorted. I haven't looked it up myself but there's gotta be a manual mechanism to release the shift lever to put in neutral as a failsafe. Probably in the manual. Usually you have to turn a hidden lock under the shifter trim etc.

chrisridebike8

Yup. I had to use it when my ESL died. Lift the shift boot and it's a yellow lever that unlocks the shift mechanism.

Jacked a c63

Yeah there is a way to release the trans so it goes into neutral, you gotta pull off the leather cloth part.
But the tow truck guy just came and put the car on go jacks LOL because the steering wheel was still locked and still couldn't turn left or right. So then he manually pushed it into the street and then towed it to the dealership.

The car starts but still has stupid rough idles, they haven't figured out why. And they said something is still draining the battery, they have to find the electrical issue.

Jasonoff

Where/how did you store the car? Could rodents have gotten into the engine bay?

chrisridebike8

Jacked a c63

its on my driveway, i don't think so because there aren't any rodents around my area. Been living here for over 10 years haven't seen any.

Finding the wiring issue is a nightmare they said

Jacked a c63

I thought about that too but then i realize I always have my switch on off, never on auto.

I thought maybe it was the parking lights or eyebrows but the dealership said thats very unlikely.

Rojasvargas22

Jasonoff

A bad key was draining your car battery?