'14 GL 450 M278 P012D
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Joined: Aug 2016
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GL450
'14 GL 450 M278 P012D
Wondering if anyone had this issue. I am getting P012D - Turgocharger/Supercharger Inlet Pressure Sensor Circuit High.
I had turbo pressure sensor issue about a year ago and got it replaced. Funny thing is, the code typically comes when the engine is cold and the weather is cold. When the engine is warm, I don't get the CEL. After deleting the CEL, it may be fine for a few days but with the temps dipping below recently in the NE, it is certainly throwing CEL more often.
The question is, what can cause the Pressure Sensor voltage to go high when cold?
thanks
I had turbo pressure sensor issue about a year ago and got it replaced. Funny thing is, the code typically comes when the engine is cold and the weather is cold. When the engine is warm, I don't get the CEL. After deleting the CEL, it may be fine for a few days but with the temps dipping below recently in the NE, it is certainly throwing CEL more often.
The question is, what can cause the Pressure Sensor voltage to go high when cold?
thanks
Thread Starter
Junior Member
Joined: Aug 2016
Posts: 42
Likes: 14
GL450
The CEL light was sporadic but now it is permanent. A couple of days ago, for the first time the engine hesitated during acceleration with sudden acceleration. Now i am getting both P012D as well as P012C.
P012D = Turgocharger/Supercharger Inlet Pressure Sensor Circuit High
P012C = Turgocharger/Supercharger Inlet Pressure Sensor Circuit Low
I replaced the turbo pressur sensor about a year ago so I will go ahead and replace the MAP sensor this time before fiddling with the fuel pump.
I was looking for the location of the MAP sensor. Found a few diagrams but nothing i liked. Then I found this: https://www.vrpspeed.com/vrp-m157-m2...install-guide/
Great step by step instruction for those looking to replace the MAP sensor.
P012D = Turgocharger/Supercharger Inlet Pressure Sensor Circuit High
P012C = Turgocharger/Supercharger Inlet Pressure Sensor Circuit Low
I replaced the turbo pressur sensor about a year ago so I will go ahead and replace the MAP sensor this time before fiddling with the fuel pump.
I was looking for the location of the MAP sensor. Found a few diagrams but nothing i liked. Then I found this: https://www.vrpspeed.com/vrp-m157-m2...install-guide/
Great step by step instruction for those looking to replace the MAP sensor.
Thread Starter
Junior Member
Joined: Aug 2016
Posts: 42
Likes: 14
GL450
Here is the update.
I replaced the passenger side MAP sensor using the install guide i posted. that cleared up the CEL. there is another MAP sensor on the driver's side. this one is on the back of the intake air filter housing. i decided to replace that as well.
i gotta say, the engine runs much smoother. worth the time and money i would say.
I replaced the passenger side MAP sensor using the install guide i posted. that cleared up the CEL. there is another MAP sensor on the driver's side. this one is on the back of the intake air filter housing. i decided to replace that as well.
i gotta say, the engine runs much smoother. worth the time and money i would say.
