# Magnetometer calibration not showing for external mag **URL:** \ **Category:** PX4 Autopilot\ **Created:** [November 5, 2019, 6:11pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727 "2019-11-05T18:11:07Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Bunborn](https://discuss.px4.io/user_avatar/discuss.px4.io/bunborn/32/5035_2.png) [@Bunborn](https://discuss.px4.io/u/Bunborn)\ **Post date:** [November 5, 2019, 6:11pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/1 "2019-11-05T18:11:07Z")
I’m using a pixhawk 4 with px4 v1.9.2 and a Zubax GNSS 2 over UAVCAN. I’ve tried doing the calibration a dozen times in different settings, I re-flashed the pixhawk, changed settings now on the Zubax to no affect. The calibration finishes but the scaling / offsets parameters never fill out for the external compass. The GPS itself works no problem and can accurately get location and connect to satellites. ![calMag](https://discuss.px4.io/uploads/default/original/2X/c/c77f1b321a1faffffc4e26f8351a6b1916138ed3.png) Any ideas? Or even ways of just disabling this second external compass so my quad is not grounded? ---
**Author:** ![hamishwillee](https://discuss.px4.io/user_avatar/discuss.px4.io/hamishwillee/32/3469_2.png) [@hamishwillee](https://discuss.px4.io/u/hamishwillee)\ **Post date:** [November 5, 2019, 9:21pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/2 "2019-11-05T21:21:48Z")
Don’t know about why scaling might not work, but you can disable compasses using [CAL\_MAGn\_EN](http://docs.px4.io/master/en/advanced_config/parameter_reference.html#CAL_MAG2_EN). ---
**Author:** ![JulianOes](https://discuss.px4.io/user_avatar/discuss.px4.io/julianoes/32/30_2.png) [@JulianOes](https://discuss.px4.io/u/JulianOes)\ **Post date:** [November 6, 2019, 8:40am UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/3 "2019-11-06T08:40:03Z")
So, how many mags do you have? It shows 3 internal mags, is that right? And can you also show the output of `listener sensor_mag`? ---
**Author:** ![Bunborn](https://discuss.px4.io/user_avatar/discuss.px4.io/bunborn/32/5035_2.png) [@Bunborn](https://discuss.px4.io/u/Bunborn)\ **Post date:** [November 6, 2019, 5:39pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/4 "2019-11-06T17:39:27Z")
It should just be two (one internal and one external). The Pixhawk 4 compass and the compass onboard the GPS (Zubax GNSS 2). Just for clairty sake, I changed the primary mag back to what it defaulted to (setting MAG1 as MAG\_PRIME) ![image](https://discuss.px4.io/uploads/default/original/2X/4/46262bd9a45a34e05e60ad0c7bdbbf2faf40cfa9.png) Here is the output for listener sensor\_mag ![image](https://discuss.px4.io/uploads/default/original/2X/c/c42dc4ad0fb58ee7adb44e48cfd5c87026203823.png) So not sure why these other mag’s are showing up but with limited parameters? Or why the gps compass isn’t appearing. It was a couple weeks ago but I swear when I tried these commands in the past it did show a second compass. I have 3 GPS modules so I am trying another one but have the same result. ---
**Author:** ![Bunborn](https://discuss.px4.io/user_avatar/discuss.px4.io/bunborn/32/5035_2.png) [@Bunborn](https://discuss.px4.io/u/Bunborn)\ **Post date:** [November 6, 2019, 6:07pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/5 "2019-11-06T18:07:34Z")
Here is the mag’s - still showing 3 internal ones - after I changed to a new GPS module. ![image](https://discuss.px4.io/uploads/default/original/2X/2/281f0d9394487af9e7d8deadac878dc859038816.png) Note that the external mag/gps is connected over UAVCAN so I changed that parameter. GPS reading itself is still good. ![image](https://discuss.px4.io/uploads/default/original/2X/7/7708e26e15ae80f3e7d90738b3a35e377e2c1b8f.png) If I unplug the GPS while it is on I get a MAG1 failure notice in Qgroundcontrol. ![image](https://discuss.px4.io/uploads/default/original/2X/d/d2f5f43477f3b2b01056923dd69f75fddb3baf4c.png) ---
**Author:** ![Bunborn](https://discuss.px4.io/user_avatar/discuss.px4.io/bunborn/32/5035_2.png) [@Bunborn](https://discuss.px4.io/u/Bunborn)\ **Post date:** [November 6, 2019, 7:16pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/6 "2019-11-06T19:16:34Z")
Sorry for posting a slew of updates, I also tried it with a completely new pixhawk 4 on 1.9.2 stable connected to a new zubax gnss 2 with the same results. The mag1 parameters **not** showing up after calibration. If I unplug the gps and do calibration, it will then not arm when gps back plugged in as ‘mag 1 is uncalibrated’. (re-calibrating then adds in the phantom mag id and mag1 rot to no rotation) I feel like a lost dog. I have a log file of me just moving the quad around for the ‘IMU’ and ‘IMU2’ (IMU2 just never moves from zero but IMU works normally). I can upload it but not sure how on here ---
**Author:** ![JulianOes](https://discuss.px4.io/user_avatar/discuss.px4.io/julianoes/32/30_2.png) [@JulianOes](https://discuss.px4.io/u/JulianOes)\ **Post date:** [November 7, 2019, 2:48pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/7 "2019-11-07T14:48:27Z")
Can you try with latest beta/v1.10 and see if it’s any better? And also check `listener sensor_mag` there again. ---
**Author:** ![Bunborn](https://discuss.px4.io/user_avatar/discuss.px4.io/bunborn/32/5035_2.png) [@Bunborn](https://discuss.px4.io/u/Bunborn)\ **Post date:** [November 7, 2019, 6:18pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/8 "2019-11-07T18:18:58Z")
In the latest beta (4) on 1.1.0 `listener sensor_mag` does show both mags ! ![image](https://discuss.px4.io/uploads/default/original/2X/2/2f188fb54ef9c1ec7accea6cb4856c0d1f624e9e.png) However **after I then recalibrated** it now SOMETIMES seems to show only the external mag for `listener sensor_mag` ![image](https://discuss.px4.io/uploads/default/original/2X/7/7468b22e2a6325bca1a1de271fe73c53853234c0.png) ![image](https://discuss.px4.io/uploads/default/original/2X/f/f0ba7fbb78b2a4ee41be825e4c2dd39908a21be3.png) But after I rebooted it again it showed both ![image](https://discuss.px4.io/uploads/default/original/2X/8/860a87e7d55e7a7807286d0e9de9e51c28d6fe20.png) Finally, thanks so much for the help thus far. It does allow me to arm ! I’m very thankful However any chance do you know what commits / code changes might be related to this? I want to modify px4 a bit myself but would prefer not to build off a beta branch 🙂 Thanks! ---
**Author:** ![JulianOes](https://discuss.px4.io/user_avatar/discuss.px4.io/julianoes/32/30_2.png) [@JulianOes](https://discuss.px4.io/u/JulianOes)\ **Post date:** [November 8, 2019, 2:19pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/9 "2019-11-08T14:19:13Z")
> [@Bunborn](#): > > However any chance do you know what commits / code changes might be related to this? That’s hard to say. I would check what changes have gone into the respective driver that you’re using but also into bugfixes for the `listener` command. It might be both. ---
**Author:** ![Abdulsamet\_TUTUNCU](https://discuss.px4.io/user_avatar/discuss.px4.io/abdulsamet_tutuncu/32/7634_2.png) [@Abdulsamet\_TUTUNCU](https://discuss.px4.io/u/Abdulsamet_TUTUNCU)\ **Post date:** [March 28, 2021, 8:55pm UTC](https://discuss.px4.io/t/magnetometer-calibration-not-showing-for-external-mag/13727/10 "2021-03-28T20:55:50Z")
Hi! I have HERE3, Pixhawk Cube Orange and I connected Here 3 with can1 port. Altough I cant see external compass. What should I do to use external compass? That topic is why I want to use external compass: [If I give higher thr 2 motors are spin slowly and stop issue - #2 by Retro-meb](https://discuss.px4.io/t/if-i-give-higher-thr-2-motors-are-spin-slowly-and-stop-issue/21670/2) ![Screenshot from 2021-03-28 23-54-00](https://discuss.px4.io/uploads/default/original/2X/1/17c1c3240c915c99b1e3f52dc7669d87f4e042b7.png)