# Debugging steps for: "Pre-arm Check Failure: Compass Sensor 0 Missing"

Source: https://forum.modalai.com/topic/5378/debugging-steps-for-pre-arm-check-failure-compass-sensor-0-missing
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2026-08-13 14:21:22 UTC by brandon
Replies: 3 · Views: 242

## brandon · 2026-08-13 14:21:22 UTC

Hello,

I've successfully flown my Starling 2 Max maybe 15 times now. Today I powered on the drone and received the status message:

Pre-arm Check Failure: Compass Sensor 0 Missing

I cannot fly the vehicle anymore. Can the engineering team provide some debugging steps to isolate what has failed or is going wrong?

So far I swapped out the GPS unit with a second Starling 2 Max that I have, but the Pre-arm message remains and I cannot fly.

Thank you!

## Reply by brandon · 2026-08-13 15:07:57 UTC

Debugging steps I have done so far:
- Swapped GPS unit with another Starling 2 Max
- Inspected and re-seated connector on both sides (gps, and voxl side)
- Ssh'd into drone and run debugging commands below. 

My current hypotheses:
- The cable is broken between the gps and voxl board.
- There is a hardware issue on the voxl board so it isn't sending commands over i2c

Do you have other ideas for things I can try or ideas for what could be wrong?

voxl2:~$ px4-listener sensor_mag
never published
voxl2:~$ px4-listener sensor_gps

TOPIC: sensor_gps
 sensor_gps
    timestamp: 678990321 (0.088196 seconds ago)
    timestamp_sample: 0
    time_utc_usec: 1786650062749778
    device_id: 11272245 (Type: 0xAC, SERIAL:6 (0x00))
    lat: 396691361
    lon: -1052411998
    alt: 2071371
    alt_ellipsoid: 2049863
    s_variance_m_s: 0.12200
    c_variance_rad: 0.75099
    eph: 0.46500
    epv: 0.56300
    hdop: 0.60000
    vdop: 0.86000
    noise_per_ms: 95
    jamming_indicator: 63
    vel_m_s: 0.02500
    vel_n_m_s: 0.00600
    vel_e_m_s: 0.02500
    vel_d_m_s: -0.01500
    cog_rad: 6.06156
    timestamp_time_relative: 0
    heading: nan
    heading_offset: 0.00000
    heading_accuracy: 0.00000
    rtcm_injection_rate: 0.00000
    automatic_gain_control: 0
    fix_type: 4
    jamming_state: 1
    spoofing_state: 1
    vel_ned_valid: True
    satellites_used: 24
    selected_rtcm_instance: 0

voxl2:~$ cat /etc/modalai/voxl-px4.conf
#!/bin/bash
#
# voxl-px4 Configuration File
#
# AIRFRAME:
#     Tell PX4 which AIRFRAME to use.
#     Options include: [MULTICOPTER, FIXED_WING]
#
# GPS:
#     Tell PX4 which GPS to use. If there is no GPS unit use NONE. Otherwise
#     choose AUTODETECT and the startup script will attempt to automatically
#     configure the GPS, magnetometer, and status LED
#     Options include: [NONE, AUTODETECT]
#
# RC:
#     Tell PX4 which RC transmitter to use.
#     Use EXTERNAL when getting RC control from external Mavlink messages (e.g Via QGC)
#     Options include: [SPEKTRUM, CRSF_MAV, CRSF_RAW, M0065_SBUS, EXTERNAL, FAKE_RC_INPUT]
#
# ESC:
#     Tell PX4 which type of ESC to use.
#     Options include: [VOXL_ESC, VOXL2_IO_PWM_ESC]
#
# POWER_MANAGER:
#     Tell PX4 which power manager to use.
#     Use NONE for ModalAI Mini-ESC since the ESC driver handles PM.
#     Use EXTERNAL when not using the ModalAI APM power manager to power the board
#       This also just disables the voxlpm driver, same as the NONE option
#     Options include: [VOXLPM, EXTERNAL, NONE]
#
# AIRSPEED_SENSOR:
#     Tell PX4 which airspeed sensor peripheral to use.
#     Note: The sensor will be started on external I2C port on voxl2
#     Options include: [NONE, MS4525DO]
#
# DISTANCE_SENSOR:
#     Tell PX4 which distance sensor peripheral to use.
#     Note: The sensor will be started on the RC port so it is only
#           really possible to use it when using external RC.
#     Options include: [NONE, LIGHTWARE_SF000]
#
# OSD:
#     Tell PX4 whether to enable OSD (on-screen display).
#     Options include: [ENABLE, DISABLE]
#
# DAEMON_MODE:
#     Tell PX4 whether to enable daemon mode.
#     Options include: [ENABLE, DISABLE]
#
# SENSOR_CAL:
#     Tell PX4 where to source sensor calibration information.
#     Options include: [ACTUAL, FAKE]
#
# ARTIFACT_MODE:
#     Do not allow artifacts to be saved to disk. Will not start the logging
#     module, will delete any current log files, and will delete the data manager file.
#     Options include: [ENABLE, DISABLE]
#
# EXTRA_STEPS:
#     Optional field that allows a user to define custom commands to be run by PX4 on boot.
#     Must be a valid bash array as seen below
#     Example: EXTRA_STEPS=( "qshell gps start" "qshell commander mode manual" )
#
#
AIRFRAME=MULTICOPTER
GPS=AUTODETECT
RC=GHST
ESC=VOXL_ESC
POWER_MANAGER=NONE
AIRSPEED_SENSOR=NONE
DISTANCE_SENSOR=NONE
OSD=DISABLE
DAEMON_MODE=ENABLE
SENSOR_CAL=ACTUAL
ARTIFACT_MODE=DISABLE
EXTRA_STEPS=()

voxl2:~$ voxl-version
────────────────────────────────────────────────────────────────────────────────
system-image: 1.8.06-M0054-14.1a-perf
kernel:       #1 SMP PREEMPT Wed Oct 22 04:13:18 UTC 2025 4.19.125
────────────────────────────────────────────────────────────────────────────────
hw platform:  M0054
mach.var:     1.0.1
SKU:          MRB-D0012-4-V2-C29-T9-M28-X0
────────────────────────────────────────────────────────────────────────────────
voxl-suite:   1.6.3
────────────────────────────────────────────────────────────────────────────────
Packages:
Repo:  http://voxl-packages.modalai.com/ ./dists/qrb5165/sdk-1.6/binary-arm64/
Last Updated: 2026-07-29 21:29:05
WARNING: repo file has changed since last update,
	packages may have originated from a different repo
List:
libfc-sensor                   1.0.9
libmodal-cv                    0.6.0
libmodal-exposure              0.1.4
libmodal-flow                  1.0.3
libmodal-journal               0.2.7
libmodal-json                  0.4.8
libmodal-pipe                  2.14.11
libqrb5165-io                  0.6.3
libvoxl-cci-direct             0.3.3
libvoxl-codec                  0.0.2
libvoxl-cutils                 0.1.6
modalai-slpi                   1.2.2
mv-voxl                        0.1-r0
qrb5165-bind                   0.1-r0
qrb5165-dfs-server             0.2.0
qrb5165-mini-tof-server        0.2.2
qrb5165-rangefinder-server     0.1.6
qrb5165-slpi-test-sig          01-r0
qrb5165-tflite                 2.17.2
voxl-bind-spektrum             0.1.1
voxl-camera-calibration        0.6.1
voxl-camera-server             2.2.19
voxl-ceres-solver              2:2.0.0-2
voxl-configurator              1.1.5
voxl-cpu-monitor               0.7.7
voxl-docker-support            1.3.1
voxl-elrs                      1.1.0
voxl-esc                       1.5.7
voxl-esptool                   0.2.0
voxl-feature-tracker           0.5.2
voxl-flow-server               0.3.6
voxl-gphoto2-server            0.0.10
voxl-imu-server                2.0.1
voxl-io-server                 0.0.8
voxl-jpeg-turbo                2.1.3-7
voxl-lepton-server             1.3.3
voxl-lepton-tracker            0.0.4
voxl-libgeographic             1.0.0
voxl-libgphoto2                0.0.4
voxl-libuvc                    1.0.7
voxl-logger                    0.6.1
voxl-mavcam-manager            0.6.0
voxl-mavlink                   0.1.6
voxl-mavlink-server            1.4.14
voxl-modem                     1.2.3
voxl-mongoose                  7.19.0
voxl-mpa-to-ros                0.3.9
voxl-mpa-tools                 1.5.6
voxl-nano-tracker              0.1.7
voxl-open-vins-server          0.6.0
voxl-opencv                    4.5.5-3
voxl-osd                       0.3.8
voxl-portal                    0.8.7
voxl-px4                       1.14.0-2.0.133
voxl-px4-params                0.9.0
voxl-qvio-server               1.2.3
voxl-remote-id                 0.0.9
voxl-reset-slpi                0.0.1
voxl-state-estimator           0.0.6
voxl-streamer                  0.8.0
voxl-suite                     1.6.3
voxl-tag-detector              0.1.0
voxl-tflite-server             0.5.1
voxl-utils                     2.0.2
voxl-uvc-server                0.1.7
voxl-vision-hub                1.9.21
voxl-vtx                       2.0.2
voxl-wavemux                   0.0.3
voxl2-io                       0.0.3
voxl2-security-hardening-utls  1.0-r0
voxl2-system-image             1.8.06-r0
voxl2-wlan                     1.0-r0
────────────────────────────────────────────────────────────────────────────────
voxl2:~$

voxl2:~$ px4-qshell
voxl2:~$

voxl2:~$ ist8310 status
-bash: ist8310: command not found

voxl2:~$ px4-qshell ist8310 status
INFO  [qshell] Send cmd: 'ist8310 status'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 766401772, local time: 766406205
ERROR [qshell] Command failed
voxl2:~$

voxl2:~$ grep -i -n -E "mag|ist|qmc|gps" /usr/bin/voxl-px4-start
8:echo "GPS: $GPS"
13:echo "DISTANCE SENSOR: $DISTANCE_SENSOR"
119:# Auto detect the magnetometer. If one or both of these devices
122:/bin/echo "Looking for qmc5883l magnetometer"
123:qshell qmc5883l start -R 10 -X -b 1
124:/bin/echo "Looking for ist8310 magnetometer"
125:qshell ist8310 start -R 10 -X -b 1
126:/bin/echo "Looking for ist8308 magnetometer"
128:qshell ist8308 start -R 12 -X -b 1
129:/bin/echo "Looking for iis2mdc magnetometer"
133:# GPS and magnetometer
134:if [ "$GPS" != "NONE" ]; then
136:	gps start -d /dev/ttyHS7
138:	qshell gps start
200:if [ "$DISTANCE_SENSOR" == "LIGHTWARE_SF000" ]; then
214:# Optional distance sensor on spare i2c
307:	# Also remove the data manager file that may have saved GPS waypoint information

voxl2:~$ px4-qshell qmc5883l status
INFO  [qshell] Send cmd: 'qmc5883l status'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 948521138, local time: 948523611
ERROR [qshell] Command failed

voxl2:~$ px4-qshell ist8310 status
INFO  [qshell] Send cmd: 'ist8310 status'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 961731054, local time: 961733319
ERROR [qshell] Command failed
voxl2:~$

voxl2:~$ px4-qshell ist8310 start -R 10 -X -b 1
INFO  [qshell] Send cmd: 'ist8310 start -R 10 -X -b 1'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 973342325, local time: 973345077
ERROR [qshell] Command failed

voxl2:~$ px4-qshell ist8310 status
INFO  [qshell] Send cmd: 'ist8310 status'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 989255823, local time: 989257867
ERROR [qshell] Command failed
voxl2:~$ px4-listener sensor_mag
never published

voxl2:~$ px4-qshell qmc5883l start -R 10 -X -b 1
INFO  [qshell] Send cmd: 'qmc5883l start -R 10 -X -b 1'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 1009230646, local time: 1009233503
ERROR [qshell] Command failed
voxl2:~$
voxl2:~$ px4-qshell qmc5883l status
INFO  [qshell] Send cmd: 'qmc5883l status'
INFO  [qshell] cmd returned with: -1
INFO  [qshell] qshell return value timestamp: 1009321642, local time: 1009323539
ERROR [qshell] Command failed
voxl2:~$
voxl2:~$ px4-listener sensor_mag
never published

voxl2:~$ journalctl -u voxl-px4 -b | grep -i -E "mag|ist|qmc|i2c|gps"
Aug 13 13:54:30 m0054 voxl-px4[2464]: GPS=AUTODETECT
Aug 13 13:54:30 m0054 voxl-px4[2464]: DISTANCE SENSOR=NONE
Aug 13 13:54:30 m0054 voxl-px4[2464]: GPS: AUTODETECT
Aug 13 13:54:30 m0054 voxl-px4[2464]: DISTANCE SENSOR: NONE
Aug 13 13:54:33 m0054 voxl-px4[2464]: WARN  [SPI_I2C] UnknownApp: no instance started (no device on bus?)
Aug 13 13:54:33 m0054 voxl-px4[2464]: WARN  [SPI_I2C] UnknownApp: no instance started (no device on bus?)
Aug 13 13:54:33 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Register interrupt b214f094 e612f13c b2602648
Aug 13 13:54:33 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0xb76329 12018473
Aug 13 13:54:33 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 5
Aug 13 13:54:33 m0054 voxl-px4[2464]: INFO  [muorb] icp101xx #0 on I2C bus 5
Aug 13 13:54:34 m0054 voxl-px4[2464]: Looking for qmc5883l magnetometer
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [qshell] Send cmd: 'qmc5883l start -R 10 -X -b 1'
Aug 13 13:54:34 m0054 voxl-px4[2464]: Looking for ist8310 magnetometer
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [qshell] Send cmd: 'ist8310 start -R 10 -X -b 1'
Aug 13 13:54:34 m0054 voxl-px4[2464]: Looking for ist8308 magnetometer
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [qshell] Send cmd: 'ist8308 start -R 12 -X -b 1'
Aug 13 13:54:34 m0054 voxl-px4[2464]: Looking for iis2mdc magnetometer
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [qshell] Send cmd: 'gps start'
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: qmc5883l start -R 10 -X -b 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'qmc5883l'
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0x80d09 527625
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [drivers__device] i2c probe failed
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] PX4_qshell: no instance started (no device on bus?)
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: qmc5883l start -R 10 -X -b 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: ist8310 start -R 10 -X -b 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'ist8310'
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0x60e09 396809
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [drivers__device] i2c probe failed
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] PX4_qshell: no instance started (no device on bus?)
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: ist8310 start -R 10 -X -b 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: ist8308 start -R 12 -X -b 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'ist8308'
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0xb0c09 723977
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [drivers__device] i2c probe failed
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] PX4_qshell: no instance started (no device on bus?)
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: ist8308 start -R 12 -X -b 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0xe1e09 925193
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [drivers__device] i2c probe failed
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] PX4_qshell: no instance started (no device on bus?)
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: gps start
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'gps'
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [tasks] Creating pthread gps
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [tasks] Successfully created px4 task PX4_gps with tid 2097644
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] Ok executing command: gps start
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [gps] GPS UART baudrate set to 115200
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0x7b3809 8075273
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 1
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set i2c address 0x38, fd 5
Aug 13 13:54:34 m0054 voxl-px4[2464]: ERROR [muorb] [drivers__device] i2c probe failed
Aug 13 13:54:34 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] PX4_qshell: no instance started (no device on bus?)
Aug 13 13:54:35 m0054 voxl-px4[2464]: INFO  [uORB] Advertising remote topic vehicle_gps_position
Aug 13 13:54:35 m0054 voxl-px4[2464]: INFO  [uORB] Advertising remote topic vehicle_magnetometer
Aug 13 13:54:35 m0054 voxl-px4[2464]: INFO  [uORB] Advertising remote topic sensor_preflight_mag
Aug 13 13:54:36 m0054 voxl-px4[2464]: INFO  [muorb] [gps] u-blox firmware version: SPG 5.10
Aug 13 13:54:36 m0054 voxl-px4[2464]: INFO  [muorb] [gps] u-blox protocol version: 34.10
Aug 13 13:54:36 m0054 voxl-px4[2464]: INFO  [muorb] [gps] u-blox module: MAX-M10S
Aug 13 13:54:36 m0054 voxl-px4[2464]: INFO  [muorb] [gps] GPS UART baudrate set to 115200
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [uORB] Advertising remote topic obstacle_distance
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [uORB] Advertising remote topic distance_sensor
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [gps] GPS UART baudrate set to 9600
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [gps] GPS UART baudrate set to 38400
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [gps] Got ack to initial CFG_VALSET!
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [gps] u-blox firmware version: SPG 5.10
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [gps] u-blox protocol version: 34.10
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [muorb] [gps] u-blox module: MAX-M10S
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [uORB] Advertising remote topic sensor_gps
Aug 13 13:55:06 m0054 voxl-px4[2464]: INFO  [uORB] Advertising remote topic estimator_gps_status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: ist8310 status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'ist8310'
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] Not running
Aug 13 14:10:33 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: ist8310 status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [health_and_arming_checks] Preflight: GPS Horizontal Pos Drift too high
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: qmc5883l status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'qmc5883l'
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] Not running
Aug 13 14:10:33 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: qmc5883l status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [health_and_arming_checks] Preflight: GPS Horizontal Pos Drift too high
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: ist8310 status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'ist8310'
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] Not running
Aug 13 14:10:33 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: ist8310 status
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell] qshell gotten: ist8310 start -R 10 -X -b 1
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [qshell]   arg0 = 'ist8310'
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] *** I2C Device ID 0x60e09 396809
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [drivers__device] Set up I2C bus mutex for bus 1
Aug 13 14:10:33 m0054 voxl-px4[2464]: ERROR [muorb] [drivers__device] i2c probe failed
Aug 13 14:10:33 m0054 voxl-px4[2464]: INFO  [muorb] [SPI_I2C] PX4_qshell: no instance started (no device on bus?)
Aug 13 14:10:33 m0054 voxl-px4[2464]: ERROR [muorb] [qshell] Failed to execute command: ist8310 start -R 10 -X -b 1
voxl2:~$

## Reply by brandon · 2026-08-13 15:26:21 UTC

![IMG_0502.JPG](https://forum.modalai.com/assets/uploads/files/1786634750150-img_0502.jpg)
![IMG_0503.JPG](https://forum.modalai.com/assets/uploads/files/1786634753452-img_0503.jpg)
![IMG_0504.JPG](https://forum.modalai.com/assets/uploads/files/1786634763963-img_0504.jpg)
![IMG_0505.JPG](https://forum.modalai.com/assets/uploads/files/1786634767169-img_0505.jpg)
![IMG_0506.JPG](https://forum.modalai.com/assets/uploads/files/1786634770008-img_0506.jpg)
![IMG_0507.JPG](https://forum.modalai.com/assets/uploads/files/1786634773008-img_0507.jpg)
![IMG_0508.JPG](https://forum.modalai.com/assets/uploads/files/1786634775604-img_0508.jpg)
![IMG_0509.JPG](https://forum.modalai.com/assets/uploads/files/1786634778598-img_0509.jpg)

## Reply by Eric Katzfey (ModalAI staff) · 2026-08-13 15:42:53 UTC

Can you plug the cable from the working drone into the other one? That could tell you if it's the cable.