APM 2.8 Exernal compass will not calibrate

Hi People
Im new to apm, but I just cannot get the external compass to calibrate, clicking on calibrate apm with external compass With (ROTATION_ROLL_180) selected from the drop down box, when I start live calibration the external compass will not calibrate, the internal compass will calibrate,tried to remove jumper and still got the same problem.
Apm 2.8 with plane extra 2.2 running.
Please can somebody point me in the right direction (my external compass wont :smiley: ), its driving me crazy.

Unfortunately the APM2.8 is not a genuine 3DR product so you are probably on your own with the compass issue.
The reason that your APM is not seeing the external compass is probably because the internal compass is still being seen by the firmware (you have not adequately disabled the internal compass) or the I2C buss on the APM is not functioning correctly with your external compass.

thanks for your reply, not sure by what you mean by disabling internal compass, is it done via mission planner, removing a jumper or cutting the jumper on the board?
thanks jeff

On the older 3DR APM2.5s, which had an internal compass, you would have to cut a trace on the board to disable the compass. The 3DR APM2.6 does not have an internal compass.
The APM2.8 is a clone and you are going to have to figure out what trace to cut on the board to disable the internal compass.
I do not believe that you can disable the internal compass using the MP.

Many of The clones Are garbage, eigher by skipping components, or using components that did not pass quality check and was discarded.
Attaching picture of NEO N8M module with magnetometer that could not be calibrated, in the picture the replaced megnetometer is upside town to the right, I did that for fun, but most people can’t fix such problems.