Fitment of after-market Coiltek Gold Extreme SDC coils is now expressly dealt with and will NOT void the detector warranty unless damage has been caused by the modification:
https://www.minelab.com/anzea/support/product-notices?article=439173
The original Minelab SDC coil should be refitted before returning the machine for service.
https://www.minelab.com/anzea/support/product-notices?article=439173
The original Minelab SDC coil should be refitted before returning the machine for service.