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Scott K
Scott K, ASE Master Tech/Instructor
Category: Car
Satisfied Customers: 1569
Experience:  20 yrs exp. Electrical; Driveabilty; Undercar; Airconditioning. Domestic and Foreign.
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How do I set the zone for my compass & change from ...

Resolved Question:

How do I set the zone for my compass & change from celcius to farenheit for temperature reading on my rear view mirror? 2001 chevy silverado.
Submitted: 9 years ago.
Category: Car
Expert:  Scott K replied 9 years ago.


Welcome to just answer,

Here is the information you requested below.

The temperature can be displayed by pressing the TEMP button. Pressing the TEMP button once briefly, will toggle the temperature reading on and off. To alternate the temperature reading between Fahrenheit and Celsius, press and hold the TEMP button for approximately four seconds until the display blinks °F and °C. Press and release the TEMP button to toggle between the Fahrenheit and Celsius readings. After approximately four seconds of inactivity, the display will stop blinking and display the last selection made.

Compass Calibration and Magnetic Variance

Compass Calibration

Before calibrating the compass, drive the vehicle to a area that is magnetically clean (free of large metallic objects). Also make sure there is no magnetic objects on the inside or outside of the vehicle close to the mirror.

  1. Start the engine.
  2. Press and hold the COMP switch (on/off switch if equipped with OnStar® controls) until the letter "C" or "Cal" is displayed.
  3. Drive the vehicle in circles at a speed of less than 8 km/h (5 mph) until the letter "C" or "Cal" is replaced by a proper vehicle heading. The calibration procedure is now complete.

Compass Magnetic Variation Adjustment

Magnetic variation adjustments are required when the compass displays a constant error in heading. Variation is the difference between magnetic north and true north due to geographical location.

    World Magnetic Variation Map

    Object Number: 384280  Size: MF

  1. Locate your current geographic location. Refer to the variation zone map.
  2. Turn ON the ignition, with the engine OFF.
  3. Press and hold the COMP switch (on/off switch if equipped with OnStar® controls) until a zone number appears on the compass display.
  4. Depress the COMP switch (on/off switch if equipped with OnStar® controls) to change the compass to the desired zone.
  5. After selecting your zone number, the display will show a compass heading after approximately 5 seconds.


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Customer: replied 9 years ago.
Reply to Scott K's Post: Thanks for the info on my compass. What about changing from celsius to fareheit on the temp?
Expert:  Scott K replied 9 years ago.

I forgot that on first post, and then posted an edit. refresh and it should be there if not reply back and i will repost it.