NEED HELP- Car electronic dead- cannot jump start
Thread Starter
Junior Member
Joined: Jul 2020
Posts: 64
Likes: 5
2019 Mercedes Benz G63
NEED HELP- Car electronic dead- cannot jump start
So today this happened. I have a 2014 G63 amg. W463.
I had gone to work and parked my car .
I was gone for maybe an hour and when I came back, my key fob didn’t unlock the car. I used the actual key and realized that no electronics would turn on. I tried jump starting the car, then got a charged brand new battery and swapped it in, but couldn’t get the car to show any sign of life. Not even the ignition or dashboard lights, nothing. Everything was dead.
I can’t imagine what is going on because I drove the car and parked it an hour ago. 2 weeks ago, I had got an error message saying “TC malfunction- park the car- AAS defective” . I parked the car and turned it on again and the message disappeared and never came back again. Not today even
I don’t think it’s a battery issue- it’s either a major fuse or A short somewhere- or I don’t know if there’s a transfer case issue- either way I can’t get power to the vehicle. Even if it was the main battery problem- the aux battery should have powered the lights, dashboard etc .
any ideas of what could be going on.? And where to start?
I don’t even know how to take the car out of park when I can’t power it to go into neutral.
I thought I’d ask experienced people.
thanks in advance
I had gone to work and parked my car .
I was gone for maybe an hour and when I came back, my key fob didn’t unlock the car. I used the actual key and realized that no electronics would turn on. I tried jump starting the car, then got a charged brand new battery and swapped it in, but couldn’t get the car to show any sign of life. Not even the ignition or dashboard lights, nothing. Everything was dead.
I can’t imagine what is going on because I drove the car and parked it an hour ago. 2 weeks ago, I had got an error message saying “TC malfunction- park the car- AAS defective” . I parked the car and turned it on again and the message disappeared and never came back again. Not today even
I don’t think it’s a battery issue- it’s either a major fuse or A short somewhere- or I don’t know if there’s a transfer case issue- either way I can’t get power to the vehicle. Even if it was the main battery problem- the aux battery should have powered the lights, dashboard etc .
any ideas of what could be going on.? And where to start?
I don’t even know how to take the car out of park when I can’t power it to go into neutral.
I thought I’d ask experienced people.
thanks in advance
MBWorld Fanatic!
Joined: Oct 2019
Posts: 5,156
Likes: 1,770
From: Colorado
G550
With everything dead, suspecting a main fuse as you suggest is a good place to start. But main fuses don't spontaneously blow - there has to be some abnormal fault that would induce this. Don't know how your electrical system is configured, but on my 2019, there is a main fuse mounted on top of the battery. All electrical circuits are fused beyond the main fuses and a short in any circuit would blow a smaller fuse before taking out the main fuse. The only likely exceptions are the starter and alternator, that likely connect directly to the battery through the main fuse. I'd start by having the starter and alternator checked. If the main fuse is OK, check the current sensor on the negative battery post (if equiped with one) to see if it has electrical continuity. Maybe there's a fault with the aux battery as well. Possible it could have died after 7 years.
Last edited by streborx; Aug 24, 2021 at 07:38 AM.
Thread Starter
Junior Member
Joined: Jul 2020
Posts: 64
Likes: 5
2019 Mercedes Benz G63
The battery was just changed 2 years ago. Can’t understand. Would the alternator or starter failure cause the complete shutdown of even dashboard lights??? I mean, I can’t get a single light to turn on, even after I replaced the main battery with a new one .
how to even move the car or even connect mbstar or Obr scanner when the car has no power .
thanks
how to even move the car or even connect mbstar or Obr scanner when the car has no power .
thanks
MBWorld Fanatic!
Joined: Oct 2019
Posts: 5,156
Likes: 1,770
From: Colorado
G550
The battery was just changed 2 years ago. Can’t understand. Would the alternator or starter failure cause the complete shutdown of even dashboard lights??? I mean, I can’t get a single light to turn on, even after I replaced the main battery with a new one .
how to even move the car or even connect mbstar or Obr scanner when the car has no power .
thanks
how to even move the car or even connect mbstar or Obr scanner when the car has no power .
thanks
Member
Joined: Apr 2020
Posts: 165
Likes: 39
From: NV, UT
2012 Land Rover LR4 5.0L V8 LUX HD
Break-out the multimeter and start at the battery then work your way to the fuse box(es). Get a schematic of the vehicle so you can identify parts as you go along so that when you identify where the juice stops or isn't going where it should be going, you can post your findings.
