Not one of my smartest moments
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Super Member
Joined: Jun 2012
Posts: 893
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From: New Jersey
‘16 Mercedes GLE450 amg,’15 Mercedes gla, coupe,’07 Mercedes w221,’12 Audi A
Not one of my smartest moments
So my 2007 Mercedes S550 was having a starting issue that started a month ago. The batteries (starter one under the hood and trunk battery ) were replaced 2 months ago. The alternator was also replaced within the last 6 months. I kinda ruled out the above parts. So now onto believing it was the starter i decided to buy couple of weeks a new one and was planning to have my mechanic install. The reason I believe it’s the starter is all the dashboard and electrical functions work it just doesn’t start. When I turn my key in the ignition and I get no noise at all. No clicking or anything at all. Unfortunately it snowed and I waited too long to do anything that the battery died completely in the car. Now to the worse part of my story is that apparently the only remote with the key blade insert is in the car that is completely dead. Car is also complete locked... I have a spare key fob but it doesn’t have the key blade insert. So now I need to somehow get into the car which is completely dead to retrieve the keyfob and jump start the car so I can put it in neutral and have it flat bedded to my mechanic. Anyone have any idea how I can open the hood with out remote or key insert blade?
Senior Member
Joined: Feb 2003
Posts: 443
Likes: 118
'03 S55 (79K miles)
Bummer
Your goal is to unlock the door so you can shift into neutral? and or unlock the hood or trunk to jump start the battery so that you can open the door? So, you still have a wireless key available, in hand? And you want to get power to the main battery so that the security module will come alive and recognize your key fob to unlock the door?
Do you have a spare 12V battery and jumper cables in your garage you can use to jump start or charge the MB?
I’m just guessing but maybe you could jack up the car and put it on jack stands (to be safe). Then get underneath and remove the plastic front belly pan. Then find the Vbatt 12V feed to the starter motor and hook the spare battery to it and to chassis ground. If that cable leads directly back to the big battery, you could charge it.
Full disclosure: I’m not familiar with the two-battery cars. I don’t know if what I said will work. I don’t know if the 12V feed on the starter is always live, and goes directly back to the big battery in the trunk. And even if it does, whether the security module and door locks are powered off that or the auxiliary accessories battery. Or if the aux accessories battery will charge off the trunk battery when at a healthy voltage over 12V.
But that’s all I can think of. I assume you don’t want AAA to send a tech over to “break in to the car”. Maybe somebody else has an idea.
There might be a sneaky way to pop the trunk but I would rather not contribute to the knowledge of car thieves.
If it’s parked at a convenient place with lots of space in front or behind, most flat bed truck drivers can winch it up onto their trucks with dollies under the rear wheels. Then take it to the dealer to figure it out.
Do you have a spare 12V battery and jumper cables in your garage you can use to jump start or charge the MB?
I’m just guessing but maybe you could jack up the car and put it on jack stands (to be safe). Then get underneath and remove the plastic front belly pan. Then find the Vbatt 12V feed to the starter motor and hook the spare battery to it and to chassis ground. If that cable leads directly back to the big battery, you could charge it.
Full disclosure: I’m not familiar with the two-battery cars. I don’t know if what I said will work. I don’t know if the 12V feed on the starter is always live, and goes directly back to the big battery in the trunk. And even if it does, whether the security module and door locks are powered off that or the auxiliary accessories battery. Or if the aux accessories battery will charge off the trunk battery when at a healthy voltage over 12V.
But that’s all I can think of. I assume you don’t want AAA to send a tech over to “break in to the car”. Maybe somebody else has an idea.
There might be a sneaky way to pop the trunk but I would rather not contribute to the knowledge of car thieves.
If it’s parked at a convenient place with lots of space in front or behind, most flat bed truck drivers can winch it up onto their trucks with dollies under the rear wheels. Then take it to the dealer to figure it out.
Senior Member
Joined: Feb 2003
Posts: 443
Likes: 118
'03 S55 (79K miles)
Is the parking brake on?
If you can’t find a way to get into the car (AAA or jumping via the starter motor lug to power up the security module) to shift it into neutral...Another idea is to disconnect the shift linkage to the transmission from under the car and shove the lever on the transmission into neutral position.
However, That’s pretty dangerous. The car can roll with you under it. Plus, I’m not even sure if such a lever on the transmission is even there or accessible
If you don’t die from that, then you have to figure out how to release the emergency parking brake so that it will roll.
This is all making me think you should just call a good tow truck driver who is familiar with getting nice cars onto the flatbed using dollies and winch and without damaging anything and getting it to the dealership.
However, That’s pretty dangerous. The car can roll with you under it. Plus, I’m not even sure if such a lever on the transmission is even there or accessible
If you don’t die from that, then you have to figure out how to release the emergency parking brake so that it will roll.
This is all making me think you should just call a good tow truck driver who is familiar with getting nice cars onto the flatbed using dollies and winch and without damaging anything and getting it to the dealership.
