How to interface a temperature sensor with an ESP32?

Question

Hi everyone,

I'm working on my college project titled "Temperature Monitoring System using ESP32", where I'm using a DHT11 sensor to measure temperature and humidity. I connected the sensor to my ESP32 board as follows:

1. VCC to 3.3V

2. GND to GND

2. DATA to GPIO4

I installed the Adafruit DHT library, uploaded the example sketch, and opened the Serial Monitor. But instead of getting temperature readings, it keeps printing

Failed to read from DHT sensor!

And sometimes it shows 0.00 °C, which is wrong.

I tried the following, but still couldn’t get consistent results:

1. Double-checked wiring

2. Used different GPIO pins

3. Increased delay between reads

Any help would be greatly appreciated!

This topic was modified 9 months ago by Electronix

Amelia · Answer

This issue is common with the DHT11 on ESP32. Here’s what you can try:

Use a 10K pull-up resistor between DATA and VCC (essential for signal stability).
Power the DHT11 with 5V instead of 3.3V, if your module supports it (most do).
Switch to the “DHTesp” library—it’s more reliable on ESP32 than the Adafruit one.
Double-check wiring and ensure you're using the correct GPIO number (GPIO4, not a labeled pin like D4).
Use short wires, and try another sensor if nothing works—some cheap modules are faulty.

These steps usually fix the "Failed to read from DHT sensor!" issue. If the error still persist you can comment.