diff --git a/libraries/AP_ADC/AP_ADC_HIL.cpp b/libraries/AP_ADC/AP_ADC_HIL.cpp
index 5a0cb92583..8830e6fe06 100644
--- a/libraries/AP_ADC/AP_ADC_HIL.cpp
+++ b/libraries/AP_ADC/AP_ADC_HIL.cpp
@@ -49,6 +49,11 @@ float AP_ADC_HIL::Ch(unsigned char ch_num)
 	return adcValue[ch_num];
 }
 
+// enable a channel
+void AP_ADC_HIL::enable_channel(uint8_t ch)
+{
+}
+
 // Read 6 channel values
 uint32_t AP_ADC_HIL::Ch6(const uint8_t *channel_numbers, uint16_t *result)
 {
diff --git a/libraries/AP_ADC/AP_ADC_HIL.h b/libraries/AP_ADC/AP_ADC_HIL.h
index dee48c586c..cdaae7316f 100644
--- a/libraries/AP_ADC/AP_ADC_HIL.h
+++ b/libraries/AP_ADC/AP_ADC_HIL.h
@@ -37,6 +37,7 @@ class AP_ADC_HIL : public AP_ADC
 	///
 	// Read 6 sensors at once
 	uint32_t Ch6(const uint8_t *channel_numbers, uint16_t *result);
+	void enable_channel(uint8_t ch);
 
 	///
 	// Set the adc raw values given the current rotations rates,