I am trying to use MP on a Kakute H7. I am able see that the gyro is working by looking at the data screen when the Matek gps/compass is not pluged in. When I plug in the compass I see the “bad compass health” warning. The parameter list shows no ID # for compass.
Power comes from 5v (which happens to be the 4th pad from the left and reads 4.83v) Also tx to rx4, and rx to tx 4. These are the connections shown in the kakute H7 wiring diagram. I did set compass_enable to “1”, hoping that would help. Continuity on the wires to the Matech M8Q-5883 compass/gps is good.
Does this disclose a problem:
COMPASS_AUTO_ROT,2
COMPASS_AUTODEC,0
COMPASS_CAL_FIT,32
COMPASS_CUS_PIT,0
COMPASS_CUS_ROLL,0
COMPASS_CUS_YAW,0
COMPASS_DEC,0
COMPASS_DEV_ID,0
COMPASS_DEV_ID2,0
COMPASS_DEV_ID3,0
COMPASS_DEV_ID4,0
COMPASS_DEV_ID5,0
COMPASS_DEV_ID6,0
COMPASS_DEV_ID7,0
COMPASS_DEV_ID8,0
COMPASS_DIA_X,1
COMPASS_DIA_Y,1
COMPASS_DIA_Z,1
COMPASS_DIA2_X,0
COMPASS_DIA2_Y,0
COMPASS_DIA2_Z,0
COMPASS_DIA3_X,0
COMPASS_DIA3_Y,0
COMPASS_DIA3_Z,0
COMPASS_ENABLE,1
COMPASS_EXTERN2,0
COMPASS_EXTERN3,0
COMPASS_EXTERNAL,1
COMPASS_FLTR_RNG,4
COMPASS_LEARN,0
COMPASS_MOT_X,0
COMPASS_MOT_Y,0
COMPASS_MOT_Z,0
COMPASS_MOT2_X,0
COMPASS_MOT2_Y,0
COMPASS_MOT2_Z,0
COMPASS_MOT3_X,0
COMPASS_MOT3_Y,0
COMPASS_MOT3_Z,0
COMPASS_MOTCT,0
COMPASS_ODI_X,0
COMPASS_ODI_Y,0
COMPASS_ODI_Z,0
COMPASS_ODI2_X,0
COMPASS_ODI2_Y,0
COMPASS_ODI2_Z,0
COMPASS_ODI3_X,0
COMPASS_ODI3_Y,0
COMPASS_ODI3_Z,0
COMPASS_OFFS_MAX,1800
COMPASS_OFS_X,-145.5618
COMPASS_OFS_Y,224.2914
COMPASS_OFS_Z,38.76436
COMPASS_OFS2_X,0
COMPASS_OFS2_Y,0
COMPASS_OFS2_Z,0
COMPASS_OFS3_X,0
COMPASS_OFS3_Y,0
COMPASS_OFS3_Z,0
COMPASS_OPTIONS,0
COMPASS_ORIENT,0
COMPASS_ORIENT2,0
COMPASS_ORIENT3,0
COMPASS_PMOT_EN,0
COMPASS_PRIO1_ID,0
COMPASS_PRIO2_ID,0
COMPASS_PRIO3_ID,0
COMPASS_SCALE,0.8613908
COMPASS_SCALE2,0
COMPASS_SCALE3,0
COMPASS_TYPEMASK,0
COMPASS_USE,1
COMPASS_USE2,0
Are you using ArduCopter version 4.2.2 ?
yes,arducopter 4.2.2 stable is installed
Then please post that information, we can not guess 
I gave up trying to make the matek compass work and bought another brand. That worked
Maybe you got a defective one. I have 3 of those. Pretty much the go-to for small craft although iFlight makes one now. Or it’s a re-branded Matek unit, they look a lot alike.