diff --git a/keyboards/sekigon/grs_70ec/config.h b/keyboards/sekigon/grs_70ec/config.h
index aa740e7775a..b1559fcc2f6 100644
--- a/keyboards/sekigon/grs_70ec/config.h
+++ b/keyboards/sekigon/grs_70ec/config.h
@@ -45,7 +45,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
 #define MATRIX_ROW_PINS { C6, D7, E6, B4, B5 }
-#define MATRIX_COL_PINS { S2, S1, S0, S3, S5, S7, S6, S4 }
+#define MATRIX_COL_CHANNELS { 2, 1, 0, 3, 5, 7, 6, 4 }
 #define UNUSED_PINS
 #define DISCHARGE_PIN B1
 #define ANALOG_PORT F6
diff --git a/keyboards/sekigon/grs_70ec/ec_switch_matrix.c b/keyboards/sekigon/grs_70ec/ec_switch_matrix.c
index 88e9bdabdb1..d1c2d85ac83 100644
--- a/keyboards/sekigon/grs_70ec/ec_switch_matrix.c
+++ b/keyboards/sekigon/grs_70ec/ec_switch_matrix.c
@@ -20,19 +20,9 @@
 #include "analog.h"
 #include "print.h"
 
-// sensing channel definitions
-#define S0 0
-#define S1 1
-#define S2 2
-#define S3 3
-#define S4 4
-#define S5 5
-#define S6 6
-#define S7 7
-
 // pin connections
 const uint8_t row_pins[]     = MATRIX_ROW_PINS;
-const uint8_t col_channels[] = MATRIX_COL_PINS;
+const uint8_t col_channels[] = MATRIX_COL_CHANNELS;
 const uint8_t mux_sel_pins[] = MUX_SEL_PINS;
 
 _Static_assert(sizeof(mux_sel_pins) == 3, "invalid MUX_SEL_PINS");