Introduction
Many users integrate PIR sensors with ESPHome or Tasmota on ESP8266/ESP32. After a firmware update, the sensor may stop working. This is usually due to configuration changes, not hardware failure.
Common Causes
1. Pin Mapping Changes
The new firmware may use different GPIO numbering or the pin function may have changed. In ESPHome, verify that the pin number in your YAML matches the actual connection.
2. Pull-Up/Pull-Down Configuration
Some updates change default pin modes. If your sensor requires a pull-up (open-drain) and it was previously enabled by default, a new version might require explicit configuration.
3. Debounce Settings
Newer versions may have different default debounce times. If the debounce is too long, short pulses may be ignored.
4. Inverted Logic
Some sensors output active LOW (open-drain) instead of active HIGH. The configuration may need `platform: gpio` with `inverted: true`.
5. Platform Changes
Major version updates can change how binary sensors are defined. Always check release notes.
ESPHome Configuration Fixes
Example working configuration for PIR sensor:
binary_sensor:
- platform: gpio
pin:
number: GPIO4
mode: INPUT_PULLUP
inverted: true # If sensor outputs LOW when triggered
name: "Living Room Motion"
device_class: motion
filters:
- delayed_on: 50ms
- delayed_off: 500ms
Tasmota Configuration
In Tasmota, use:
SetOption114 1 # Enable pulse counter mode
Rule1 on motion#boot do publish stat/%topic%/MOTION 1 endon
Step-by-Step Troubleshooting
- Revert to previous firmware version to confirm sensor hardware still works.
- Check ESPHome logs for errors or warnings about the pin.
- Test with a simple configuration that only reads the pin and prints state.
- Verify with a multimeter that the sensor output is actually changing.
- Compare your current YAML with the example above.
Case Study: ESPHome 2024 to 2025 Upgrade
After upgrading ESPHome from 2024.12 to 2025.2, a user’s PIR sensor stopped working. The issue was that the new version required explicit `mode: INPUT_PULLUP` whereas previously it defaulted to pull-up. Adding this line fixed it.
Conclusion
Firmware updates can change behavior. Always keep a backup of working configurations and test changes incrementally.