Wemos D1 mini pro - Sample Sketch

[superfino]

Hi all you coders! When I load the NewPingESP8266Example to my D1 mini, everything works as expected. I've adapted only the Pin assignment. After Power/off or a Reset, nothing happens at all. I've to load the code again and this happens only with this example. Any Idea what may be wrong?

[superfino]

Actually i used a RCW-0001 Ultrasonic Sensor but today i got a HC-SR04 and this one doesn't show the boot up problem mentioned. The board starts also when i remove power from the RCW-0001 and the Sensor works when i apply power after boot. Any help is appreciated.