diff --git a/src/driver/scd4x.cc b/src/driver/scd4x.cc
index dfb6ee06de791619236b6f56d948aa5b447af158..3ad34a0053f0854c02ef0ec45ab1ff3de391a85e 100644
--- a/src/driver/scd4x.cc
+++ b/src/driver/scd4x.cc
@@ -37,7 +37,7 @@ void SCD4x::read()
 	txbuf[0] = 0xec;
 	txbuf[1] = 0x05;
 
-	if (i2c.xmit(address, 1, txbuf, 9, rxbuf) == 0) {
+	if (i2c.xmit(address, 2, txbuf, 9, rxbuf) == 0) {
 		co2 = (rxbuf[0] << 8) + rxbuf[1];
 		rawTemperature = ((rxbuf[3] << 8) + rxbuf[4]);
 		rawHumidity = (rxbuf[6] << 8) + rxbuf[7];