2012 GLK350 No Start brake pedal stiff
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GLK350 2012 80,000mi
2012 GLK350 No Start brake pedal stiff
I have a 2012 GLK350 80,000 Mi.
Everything has been wonderful until today.
Drove to work, parked for 4 hours. Went out at noon and car would not start.
Brake pedal is incredibly stiff.
Will not start br button or key.
Car can be locked/unlocked/windows up & down with key fob.
Advice is greatly appreciated.
Everything has been wonderful until today.
Drove to work, parked for 4 hours. Went out at noon and car would not start.
Brake pedal is incredibly stiff.
Will not start br button or key.
Car can be locked/unlocked/windows up & down with key fob.
Advice is greatly appreciated.
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Joined: Feb 2023
Posts: 728
Likes: 271
2011 GLK 350 4Matic
The brake pedal is stiff because the engine's not running (the brake booster needs engine vacuum to assist with the pressure on the brake master cylinder).
There are a host of things that can cause a car not to start (or more accurately, cause the engine not to turn over). This is one of those cases where having a basic multimeter would be very helpful (just a quick reading to see what the battery voltage is).
Does the dash indicate that the shifter is in the Park (P) position?
There's no "key symbol" on the dash anywhere?
There are a host of things that can cause a car not to start (or more accurately, cause the engine not to turn over). This is one of those cases where having a basic multimeter would be very helpful (just a quick reading to see what the battery voltage is).
Does the dash indicate that the shifter is in the Park (P) position?
There's no "key symbol" on the dash anywhere?
MBWorld Fanatic!
Joined: Jun 2021
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From: South Texas
2014 GLK350 base model (active) ; 2001 E320 base (retired); 2001 Wrangler soft-top
The amperage required to start a vehicle is normally more than locking and unlocking doors and rolling windows 
I'd check the main battery first and its connections.
(It's doubtful the Aux battery, but check it, if that model has it)
I'd check the main battery first and its connections.
(It's doubtful the Aux battery, but check it, if that model has it)
MBWorld Fanatic!
Joined: Jan 2009
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From: Northern NJ
GLK 350 / Porsche 993
Hopefully just an old battery not having enough juice. Like others said, if the volts are below certain level it will not even try to start (no slow cranking on these cars).
