# Peripheral issue

***Copyright © Quectel Wireless Solutions Co., Ltd. 2026. All rights reserved.***

---

# Why does the display remain blank?

1. Check whether the display is supported by Quectel Pi M1.

2. Check whether the display is receiving power properly.

3. Check that the MIPI ribbon cable is firmly connected and oriented correctly.

4. Check the kernel log to confirm that the system has detected the display correctly. Run the following command to filter the log for relevant entries:

```bash
dmesg | grep -iE 'display|hdmi|dsi'
```

# What should I do if the camera does not load?

1. Check whether the camera is supported by Quectel Pi M1.

2. Check that the MIPI ribbon cable is firmly connected and oriented correctly.

3. Check whether the cam-server service is running properly. Run the following commands to query the service status:

```bash
# Query the service status. The expected status is active (running).
systemctl status cam-server

# Restart the service if it is not running properly.
systemctl restart cam-server
```

4. Check the kernel log to confirm that the system has detected the camera correctly and that the expected probe messages are present. Run the following command for troubleshooting:

```bash
dmesg | grep cam | grep -i probe
```

For example, the following log entries indicate that the IMX577 and OV9282 sensors were powered on and probed successfully:

```bash
CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:0,slave_addr: 0x34,sensor_id:0x577, is always on:0
CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:1,slave_addr: 0xc0,sensor_id:0x9281, is always on:0
```

If no probe messages appear, check whether the sensor I2C address or power-up sequence is incorrect.

# What should I do if the display resolution is incorrect?

## Check whether the hardware detects the display correctly

First, confirm that the kernel has successfully read the display's EDID (Extended Display Identification Data), which is required for resolution negotiation.

```bash
# 1. Check the connection status of all display interfaces.
for p in /sys/class/drm/card0-*/status; do echo -n "$p: "; cat $p; done

# 2. Check whether the EDID was read successfully (a nonzero file size indicates successful detection).
cat /sys/class/drm/card0-*/edid > /tmp/edid.bin
ls -lh /tmp/edid.bin
```

If the EDID file size is 0, the display did not provide valid EDID information. This commonly occurs with nonstandard displays, poor-quality HDMI cables, or loose connections.

## View the currently available resolution modes

```bash
# View the modes currently supported by the kernel DRM subsystem.
cat /sys/class/drm/card0-*/modes
```

If the target resolution (for example, 1920 × 1080) is not listed in the output, the EDID does not include that mode or the driver failed to parse it correctly.

## Analyze logs to identify the cause

```bash
dmesg | grep -i -E "drm|hdmi|msm|dpu|edid|mode"
journalctl -b | grep -Ei 'drm|dsi|dp|edid|panel|gdm|wayland' | tail -100
```

# What should I do if the camera is not detected?

1. Check that the MIPI ribbon cable is firmly connected and oriented correctly.

2. Check the kernel log to confirm that the system has detected the camera correctly and that the expected probe messages are present. Run the following command for troubleshooting:

```bash
dmesg | grep cam | grep -i probe
```

For example, the following log entries indicate that IMX577 sensor and OV9282 sensors were powered on and probed successfully:

```bash
CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:0,slave_addr: 0x34,sensor_id:0x577, is always on:0
CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:1,slave_addr: 0xc0,sensor_id:0x9281, is always on:0
```

If no probe messages appear, check whether the sensor I2C address or power-up sequence is incorrect.

```bash
dmesg | grep cam | grep -i probe
```

3. If you are using a custom camera sensor, contact Quectel Technical Support for guidance.

# What should I do if there is no sound?

## Check the hardware and connections

Check that the speaker or headphones are firmly connected.

## Confirm that the sound card is detected

Run the following command to list all sound cards detected by the system:

```bash
# List all sound cards.
cat /proc/asound/cards
```

## Check the output device settings

```bash
# View the default output device.
pactl info | grep -i default

# Set the default output device.
pactl set-default-sink low-latency0

# Set the output device port (speaker: speaker; headset: headphones).
pactl set-sink-port low-latency0 speaker
pactl set-sink-port low-latency0 headset

# Unmute the output device (0: unmuted; 1: muted).
pactl set-sink-mute low-latency0 0

# Set the volume to 80%.
pactl set-sink-volume low-latency0 80%
```

## Play test audio

```bash
gst-launch-1.0 audiotestsrc ! pulsesink
```