Code P009a

2008 MERCEDES BENZ CLS550
80,000 MILES • 2WD • AUTOMATIC
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JROCK14
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Hello, I have the car listed above w219 and I have this code P009a. I do not know where the ambient air temperature sensor is located on this particular model. Do I remove the tray under the engine? Please help, thanks.
Jul 10, 2018 at 4:59 PM
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DANNY L
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Hello, I am Danny.

I have found three air temperature sensors for your car. Two are in the interior and one on the engine. I have attached the pictures showing their location and circled in red. Hope this helps and feel free to ask questions if needed. Thanks for using 2CarPros.
Danny-
Jul 10, 2018 at 11:28 PM
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JROCK14
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Okay thank you. I thought that it was behind the grille or something? This sensor is not for the engine temperature but the outside air temperature. Is it one of these or something different? As far as I know it has to be away from the engine in some sense so it can give an accurate reading of the outside temperature and all of those sensors seem to be something else.
Jul 11, 2018 at 3:26 AM
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JROCK14
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The temperature for outside is reading to high, it reads 110 degrees when it is only 90 degrees outside and it is throwing this code: https://www.pelicanparts.com/techarticles/Mercedes-W204/35-ELEC-Ambient_Air_Tempurature_Sensor_Replacement/35-ELEC-Ambient_Air_Tempurature_Sensor_Replacement.htm

I saw this but it is not my model so I was not sure if it is the same but here is the sensor according to the code.
Jul 11, 2018 at 3:33 AM
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DANNY L
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Hello again.

That would be the B10/4 or the second picture I attached in the previous post. It is located in the dashboard. Hope this helps and let me know if you have any other questions.
Danny-
Jul 11, 2018 at 4:50 PM
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JROCK14
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B14, it is located behind the front lower grille.
Jul 12, 2018 at 6:10 AM
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DANNY L
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Hello again.

Were you able to change it? Is the problem fixed? Keep me updated.
Danny-
Jul 12, 2018 at 3:51 PM
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JROCK14
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I will be replacing it tomorrow.
Jul 12, 2018 at 4:44 PM
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DANNY L
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Hello again.
Cool, keep me updated.
Danny-
Jul 12, 2018 at 5:03 PM