ESPHome reporting I2C bus errors on AirGradient Pro; no temp & humidity results

I have been using the AirGradient Pro presoldered edition with ESPHome
(with a slightly tweaked config from ESPHome-AirGradient/air-gradient-pro-presoldered.yaml at main · ajfriesen/ESPHome-AirGradient (

It’s been working well for some time, but recently, with the ESPHome updates, something’s gone wrong with the I2C bus startup:

[09:16:16][C][i2c.arduino:053]: I2C Bus:
[09:16:16][C][i2c.arduino:054]:   SDA Pin: GPIO4
[09:16:16][C][i2c.arduino:055]:   SCL Pin: GPIO5
[09:16:16][C][i2c.arduino:056]:   Frequency: 50000 Hz
[09:16:16][C][i2c.arduino:065]:   Recovery: failed, SDA is held low on the bus
[09:16:16][I][i2c.arduino:069]: Results from i2c bus scan:
[09:16:16][E][i2c.arduino:077]: Unknown error at address 0x08
[09:16:16][E][i2c.arduino:077]: Unknown error at address 0x09
[09:16:16][E][i2c.arduino:077]: Unknown error at address 0x0A
[09:16:16][E][i2c.arduino:077]: Unknown error at address 0x0B
[09:16:16][E][i2c.arduino:077]: Unknown error at address 0x0C
[09:16:16][E][i2c.arduino:077]: Unknown error at address 0x0D
[09:16:17][C][sht3xd:029]: SHT3xD:
[09:16:17][C][sht3xd:030]:   Address: 0x44
[09:16:17][E][sht3xd:032]: Communication with SHT3xD failed!

Anybody have an idea about what might have failed?

You could try and older version of esphome or change the frequency of i2c as what your screenshot shows isn’t the default if I remember right