No I2C device at address

[PersephoneKarnstein]

tried the example exactly as shown on https://learn.adafruit.com/adafruit-max17048-lipoly-liion-fuel-gauge-and-battery-monitor/python-circuitpython using a Adafruit MAX17048 LiPoly / LiIon Fuel Gauge and Battery Monitor and Raspberry Pi 4B. Everything was correctly connected; LEDs were lit, etc. Got the following error on the second line of the example.

>>> import time
>>> import board
>>> import adafruit_max1704x
>>> 
>>> i2c = board.I2C()  # uses board.SCL and board.SDA
>>> 
>>> i2c
<busio.I2C object at 0x7f819b6490>
>>> max17 = adafruit_max1704x.MAX17048(i2c)
Traceback (most recent call last):
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_bus_device/i2c_device.py", line 175, in __probe_for_device
    self.i2c.writeto(self.device_address, b"")
  File "/home/persephone/env/lib/python3.11/site-packages/busio.py", line 215, in writeto
    return self._i2c.writeto(address, buffer, stop=True)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_blinka/microcontroller/generic_linux/i2c.py", line 60, in writeto
    self._i2c_bus.write_bytes(address, buffer[start:end])
  File "/home/persephone/env/lib/python3.11/site-packages/Adafruit_PureIO/smbus.py", line 303, in write_bytes
    self._device.write(buf)
OSError: [Errno 121] Remote I/O error

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_bus_device/i2c_device.py", line 181, in __probe_for_device
    self.i2c.readfrom_into(self.device_address, result)
  File "/home/persephone/env/lib/python3.11/site-packages/busio.py", line 205, in readfrom_into
    return self._i2c.readfrom_into(address, buffer, stop=True)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_blinka/microcontroller/generic_linux/i2c.py", line 67, in readfrom_into
    readin = self._i2c_bus.read_bytes(address, end - start)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/persephone/env/lib/python3.11/site-packages/Adafruit_PureIO/smbus.py", line 170, in read_bytes
    return self._device.read(number)
           ^^^^^^^^^^^^^^^^^^^^^^^^^
OSError: [Errno 5] Input/output error

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_max1704x.py", line 110, in __init__
    self.i2c_device = i2c_device.I2CDevice(i2c_bus, address)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_bus_device/i2c_device.py", line 62, in __init__
    self.__probe_for_device()
  File "/home/persephone/env/lib/python3.11/site-packages/adafruit_bus_device/i2c_device.py", line 184, in __probe_for_device
    raise ValueError("No I2C device at address: 0x%x" % self.device_address)
ValueError: No I2C device at address: 0x36

i2cdetect results are below

(env) persephone@raspberrypi:~ $ ls /dev/i2c*
/dev/i2c-1  /dev/i2c-20  /dev/i2c-21
(env) persephone@raspberrypi:~ $ sudo i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         -- -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- -- --                         
(env) persephone@raspberrypi:~ $ sudo i2cdetect -y 20
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         08 09 0a 0b 0c 0d 0e 0f 
10: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 
20: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 
30: -- -- -- -- -- -- -- -- 38 39 3a 3b 3c 3d 3e 3f 
40: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: 60 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 
70: 70 71 72 73 74 75 76 77                         
(env) persephone@raspberrypi:~ $ sudo i2cdetect -y 21
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         08 09 0a 0b 0c 0d 0e 0f 
10: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 
20: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 
30: -- -- -- -- -- -- -- -- 38 39 3a 3b 3c 3d 3e 3f 
40: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: 60 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 
70: 70 71 72 73 74 75 76 77    

[caternuson]

Please post in the forums with photos of your setup showing how everything is connected:
https://forums.adafruit.com/

[Thynix]

I had this problem using CircuitPython from an ESP32-S2. When I plugged a battery into the MAX17048 board, it started appearing on I2C. Strange, I'd expect it to read 0V instead?

The corresponding Adafruit Forum post is here.