How Can I Force Compass Re-calibration?

Do you get the error with both magnetic and true north?

Hold the phone horizontally away from the body and make a figure eight motion with it.

I wish they would add a calibrate button in settings for the compass.
Try launching compass around yor desktop computer or wifi router they tend to cause mine to go into recalibrate mode.
In fact anytime you don't want it to recalibrate it will 🙂

iphone3ger wrote:
In fact anytime you don't want it to recalibrate it will 🙂

Hallelujah! Someone else that is having the same thing happen to them! How many other people are seeing this???

OBTW, To the original poster: I too often get into a state where things are 90 or even 180 degrees off. I keep wondering if I got a bunk 3GS or if this all is common?

I basically cannot use the digital compass inside a car. There are just too many magnetic fields inside that the compass keep prompting for calibration. I finally understand why GPS navigation programs never use digital compass and replace it by vector calculations. Magnetic interference is just everywhere including the car engine, power door, power window, AC fan, etc......

I'm very disappointed about the digital compass inside a vehicle.

I have a phone that is being replaced(waiting for new one overnight) and the compass changes when lying flat and brought up to a standing/verticle position, by 20 degrees. It is so inaccurate compared to the others I've seen...

You can force a compass calibration by a magnet, take one of your kitchen magnets and hold it under the iPhone.

The compass in The iPhone is a brilliant 3 axis sensor system, but it needs to be calibrated. The compass will self calibrate overtime when exposed to the earth field from all directions. Up, down sides, front, back. Sometimes it gets thrown off and needs a little help to calibrate faster.

Be careful with some calibration instructions using the term "figure 8". Do this, pretend the iPhone is a toy car and drive it around on figure 8 track. The iPhone needs to be exposed to the earth field from all directions. This will give the compass a 2D calibration.

You can see a video just search on "youtube iPhone compass calibration lysfyr"

Many other videos show a waving of the iPhone the will only expose the compass to the earth magnetic field from one direction and not the full 360++ degs.

I haven't made any attempt to use my compass other than to note it was there and seemed to point in the right direction. I've had my new phone for a week now and certainly have exposed it to normal magnetic fields (in the car, computers, etc.)

After reading this post, I checked it with a very accurate compass that I own (designed for offshore navigation) and I must say that I'm surprised how accurate the IP compass appears to be. I sighted on a distance object at a mag bearing of 190 degrees. My IP also checks in within a degree of 190.

No, I'm not going to us my IP to navigate a sailboat to Hawaii, but it appears that I could and CERTAINLY could if the GPS would also give me a reasonable lat/long position.

Yes, I agree. A magnet is your best bet. If I put my iPhone close to the magnet on my mac it will ask to be calibrated.

Simply use your bundle iPhone headset, magnet
inside earphone is enough to bring the re-calibration
page. But, don't try to re-calibrate your compass
if there is obvious magnetic interference, e.g.
inside your car, there is a support doc for that.
http://support.apple.com/kb/TS2767

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