Grove Temperature and Humidity Sensor (High Accuracy AndMini-v1.0) Temp -50.00°C, Hum -24.00%

Hello everyone,

I’m encountering an issue with the Grove Temperature and Humidity Sensor (High Accuracy AndMini-v1.0) when using it with an Arduino Uno. The sensor is giving me strange readings - it shows -50.00°C for temperature and -24.00% for humidity.

I’ve checked my code and connections, but I’m still getting these incorrect values. Has anyone else experienced this issue before? If so, do you know what might be causing it and how to fix it?

This is the code I used :

#include <TH02_dev.h>

#include “Arduino.h”

#include “Wire.h”

#include “THSensor_base.h”

#define ShowSerial Serial

#ifdef AVR

#include <SoftwareSerial.h>

SoftwareSerial SSerial(2, 3); // RX, TX

#define COMSerial Serial

#define ShowSerial Serial

TH02_dev TH02;

#endif

#ifdef ARDUINO_SAMD_VARIANT_COMPLIANCE

#define COMSerial Serial1

#define ShowSerial SerialUSB

TH02_dev TH02;

#endif

#ifdef ARDUINO_ARCH_STM32F4

#define COMSerial Serial

#define ShowSerial SerialUSB

TH02_dev TH02;

#endif

void setup() {

ShowSerial.begin(9600);        // start serial for output

ShowSerial.println("****TH02_dev demo by seeed studio****\n");

/* Power up,delay 150ms,until voltage is stable */

delay(150);

/* Reset HP20x_dev */

TH02.begin();

delay(100);

/* Determine TH02_dev is available or not */

ShowSerial.println("TH02_dev is available.\n");

}

void loop() {

float temper = TH02.ReadTemperature();

ShowSerial.print("Temperature: ");

ShowSerial.print(temper);

ShowSerial.println("C\r\n");

//Serial.print("%\t");

float humidity = TH02.ReadHumidity();

ShowSerial.print("Humidity: ");

ShowSerial.print(humidity);

ShowSerial.println("%\r\n");

delay(1000);

}

I appreciate any help or insights you can provide!

Thank you.

Are you exactly working according to this wiki page? Or made some changes?

Hello,

Thank you for your response !
Yes, I’m working exactly according to that wiki page and I followed all the steps that are mentionned.

Can we see how you wired it?


This is how I wired it. I connected SDA to A4 and SCL to A5 .

Since you have already shared your connection, I hope seeedstudio will take a look and suggest if any other components like pull-up resistors are needed. I have found another thread in github which discusses about TH02 sensor giving negative value:
Grove TH02 Humidity/Temperature sensor reporting incorrect (minus) values · Issue #1658 · rwaldron/johnny-five · GitHub
You may find some clues from here. Also, you can cross check the temperature and humidity data with an Arduino and another temperature and humidity sensor like DHT22 or DHT11(if available). Here is a simple test code: Ldr and DHT22 Home-Automation - Share Project - PCBWay

Thank you for sharing this information and providing additional resources regarding the TH02 sensor issue. I’ll definitely take a look at the GitHub thread you’ve mentioned and explore the suggestions provided. Cross-checking the temperature and humidity data with another sensor like the DHT22 or DHT11 sounds like a good idea too, but unfortunately, I don’t have access to these sensors at the moment.

I truly appreciate your help !