Mercedes-Benz 420SEL Ambient Temperature Sensor (Switch) Replacement at your home or office.

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Ambient Temperature Sensor (Switch) Replacement Service

How much does a Ambient Temperature Sensor (Switch) Replacement cost?

On average, the cost for a Mercedes-Benz 420SEL Ambient Temperature Sensor (Switch) Replacement is $324 with $125 for parts and $199 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1988 Mercedes-Benz 420SELV8-4.2LService typeAmbient Temperature Sensor (Switch) ReplacementEstimate$490.66Shop/Dealer Price$589.71 - $804.16
1987 Mercedes-Benz 420SELV8-4.2LService typeAmbient Temperature Sensor (Switch) ReplacementEstimate$448.66Shop/Dealer Price$547.77 - $762.27
1990 Mercedes-Benz 420SELV8-4.2LService typeAmbient Temperature Sensor (Switch) ReplacementEstimate$448.66Shop/Dealer Price$547.77 - $762.26
1991 Mercedes-Benz 420SELV8-4.2LService typeAmbient Temperature Sensor (Switch) ReplacementEstimate$448.66Shop/Dealer Price$547.69 - $762.12
1989 Mercedes-Benz 420SELV8-4.2LService typeAmbient Temperature Sensor (Switch) ReplacementEstimate$448.66Shop/Dealer Price$547.83 - $762.37
1986 Mercedes-Benz 420SELV8-4.2LService typeAmbient Temperature Sensor (Switch) ReplacementEstimate$448.66Shop/Dealer Price$547.77 - $762.26
Show example Mercedes-Benz 420SEL Ambient Temperature Sensor (Switch) Replacement prices

What is the Ambient Temperature Sensor (Switch) all about?

Modern automotive HVAC systems have advanced by leaps and bounds over those used just a few years ago. Today, many high and even mid-range cars offer automatic climate control. This function basically allows you to “set it and forget it,” allowing the car’s computer to control the heating and cooling based on your preferred interior temperature. In order to do this, the computer needs information about not only the temperature inside the car, but also the ambient temperature outside the car.

The ambient temperature sensor (switch) is located either behind the front grille or in the front bumper. Its only job is to monitor air temperature (which it does through increasing/decreasing resistance in response to temperature fluctuations). This information is transmitted to the car’s computer, which then adjusts the climate control to meet your specifications.

If the ambient temperature sensor is damaged or fails, the car’s computer will not be able to automatically control the HVAC system, and the heater and air conditioner will only work in manual mode.

Keep in mind:

  • Because of its location, the ambient temperature sensor can be easily damaged in even minor front-end collisions.
  • Sensor failure is common even without an accident.

How it's done:

  • The ambient temperature sensor switch is verified to see if it needs to be replaced
  • The defective ambient temperature sensor switch is removed
  • The new ambient temperature sensor switch is installed
  • The ambient temperature sensor switch is tested for operation
  • The vehicle is tested to ensure proper operation of the ambient temperature sensor switch

Our recommendation:

Without the information provided by the ambient temperature sensor, your car’s computer does not have sufficient data to control the interior temperature, and will revert to manual HVAC control. You’ll still be able to use your air conditioner and heater, but only in manual mode, not in auto. If you suspect a problem with the ambient temperature sensor, have it diagnosed by one of our expert mechanics and replaced if necessary.

What common symptoms indicate you may need to replace the Ambient Temperature Sensor (Switch)?

  • HVAC auto mode will not work
  • HVAC auto mode produces delivers inconsistent/incorrect operation
  • HVAC will only work in manual mode
  • Outside temperatures may display incorrectly

How important is this service?

Having automatic climate control is definitely a convenience, but not critical to the operation of your vehicle. The heater will still operate to clear the windows and provide heating and cooling on manual mode. If the ambient temperature sensor is faulty, have it replaced.

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Excellent Rating

(18)

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Carlos

28 years of experience
502 reviews
Carlos
28 years of experience
Mercedes-Benz 420SEL V8-4.2L - Serpentine/Drive Belt - Ontario, California
Carlos came on time (unlike others who cancelled the appointment several times). He came, TWICE because of my car needed more parts than expected. Great job, friendly, very professional, I HIGHLY recommend him, and will make sure next time - if needed - he will be the one I ask for. Thank you Carlos

Dwaine

45 years of experience
39 reviews
Dwaine
45 years of experience
Mercedes-Benz 420SEL V8-4.2L - Oil Cooler Hose (Automatic Transmission) - Brandon, Florida
Great experience, very polite and knowledgeable mechanic.

Desmond

20 years of experience
50 reviews
Desmond
20 years of experience
Mercedes-Benz 420SEL V8-4.2L - Valve Cover Gasket - Salinas, California
Top-notch! Timely, competent, and thorough with the 50-point inspection. I got much more out of the 50-point inspection than the initial service request---definitely above and beyond!

Marco

29 years of experience
222 reviews
Marco
29 years of experience
Mercedes-Benz 420SEL V8-4.2L - Neutral Safety Switch - Riverside, California
A life-saver

Excellent Rating

(18)

Rating Summary
17
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Number of Mercedes-Benz 420SEL services completed
198+
services done by our mechanics
TOTAL NUMBER OF EXPERT Mercedes-Benz MECHANICS
1100+
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