Turnk Will Not Open - Battery May Be Dead
 

I took my 92' 300SE for a test drive last night for about a half an hour or so. Got back home and everything was fine. Later in the evening I wanted to move the car in the drive way and everything went dead. I inserted the key as usual heard the buzzer and when I turned the key to the start position everything went dead. So, I opened the trunk and checked the battery and the positive cable was a little loose so I tightened it and the lights in the trunk came back on. Went back to start the engine, inside lights came on, I heard the buzzer turned the key to start and it went dead again. It was really dark and I didn’t feel like messing with it so, I shut the trunk and manually locked all the doors. This afternoon I went out to work on the car and the doors open but, I can not get into the trunk. I removed the back seat to see if there was a manual cable that releases the trunk and no such luck. I need to get the trunk open so I can get to the battery. Any ideas???

Ideas:

"boost" the car through the cigarette lighter socket, enough to try door locks, etc.. but not start the car

boost the car with cable to the starter motor, run it, get vacuum up, try the door locks

How do you do that?

ehopkins, look in your Owner's Manual to see if there are positive and negative terminals under the hood for the purpose of jump starting your 1992 300SE. Our 1998 E320 is equipped that way because the battery is under the rear seat. The positive terminal is enclosed in a black plastic box with a red "+" on the top, while the negative terminal is exposed and has several brown ground wires connected to it. The terminals are side by side on the driver's side.

The 92 does not have that terminal, the trunk should open with the key by trurning it 90 degrees and then pushing the button. Oherwise a trickle charger thru the lighter, but the key must be on. The other options would be to lift the passenger side front carpet and find the large battery cable from the trunk. If all that fails a little bit of pressure on the line coming from the locking pump from a bike pump.

My care does not have terminals under the hood. Thanks for your suggestion though.

Thanks Peter! Turning the key is not working. I am going to try the trickle charger through the lighter first. I should only need enough charge to build the vacuum back up and then the trunk should release.

Received some local advise from a MB Motor. Bud suggested that I use the key, turn it to the left little by little. After the 3rd try the trunk popped open. I tightened down the battery down really good and she fited right up. Thanks for all the suggestions.

A shout-out to Bud and MB Motor, you are the best!!!

MB Motors, LTD.
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