diff --git a/Testing.md b/Testing.md
index d10911f..86dac72 100644
--- a/Testing.md
+++ b/Testing.md
@@ -49,5 +49,5 @@ sudo jetson_clocks --fan
 Turn on the fan with modulated PWM
 
 ```bash
-echo 255 > /sys/devices/pwm-fan/target_pwm
+sudo echo 255 > /sys/devices/pwm-fan/target_pwm
 ```