georgeclk200

Hi everyone, I had my CLK to the garage to replace some ventilation valve hose, and when I got the car back the engine light went on, my diagnostic says "Altitude pressure sensor signal - short circuit to ground". Does anyone know what that sensor is and where is it located? What does short circuit to ground might mean?

Thank you very much

Rudeney

What is the actual code you pulled? I can look that up in SDS to see what possible diagnostic steps it guides us to.

georgeclk200

Hello! Thank you for your reply, I am using a delphi diagnostic, the fault code I get is 2013. (DTC 2013).

Thank you

Rudeney

It's either a bad sensor or a wiring problem. Here's the sensor:

georgeclk200

thanks you very much for your help I really appreciate it!
Do you also happen to know what is the attached in the green circle? I havent seen those connected for over a year and I knew I was missing something there..

Rudeney

No, I don't know where that goes. Maybe another forum member with an M271 engine can look and see? In fact, you might want to pose the question in the W203 forum as there are many more M271 engines in that model.

Russell Ormerod

Most likely vacuum supply for headlamp range adjustment

Casmige

Hey there!,

Thanks heaps for your post & helpful reply.

It helped me solve a serious Short to Ground P0105 CEL Code in my Daughters 2003 C230 Kompressor.

Although?? What you have circled?? is not the Altitude Pressure switch.....The Sensor though that is right above your Red-Square circled item is indeed in fact the Altitude sensor.

Here's where it gets sorta confusing though:

Mercedes Benz OEM part number for this Sensor (What MB calls the FORE Manifold Pressure Sensor) is the same part & part number as the "AFT" Manifold Pressure Sensor....what actually installs into the manifold at the back underneath the wiring harness for the ECM.

The Front one does in fact measure barometric Altitude pressure....& in my daughters case?? Someone previously had hooked up the Vacuum hose that normally would go to the Headlight Wiper Servo's mistakenly.

Your post got me thinking about WHY MB would call the front the "Altitude Pressure Sensor" while the rear one (Same part, Same part number) the Manifold pressure sensor.

It would ALSO explain WHY MB has the Front sensor hiding itself in a little bit of a cave that, if one hooks a vacuum hose to?? would crimp & cramp it once you screw down the sensor).

Which translated all this issue in my case?? to simple disconnecting the Vacuum hose, plugging it with a screw & leaving the FRONT Altitude Pressure Sensor without any sort of hose attached to it.

VOILA!! the CEL never came back on for the P0105 Pressure sensor Short-to-Ground Fault code.

Your post along with this thread though helped me muse & over-think the issue to a rather neat Socratic conclusion!.

Thank you!