Here are some common issues related to auto-ID of sensors you should check before going further:

A. Some older sensors are not auto-ID capable.
If you are using older sensors with round, DIN plugs and adapters, they are incapable of auto-ID. Some other sensors, such as older radiation monitors and drop counters, are also not auto-ID. You must manually set them up by choosing Sensor Setup from the Sensors menu. (LabQuest: How can I manually set up a sensor that does not auto-ID?)

B. Some newer sensors require an update to work.
Updating to the latest version of the LabQuest app can ensure any new sensors are supported. If the issue is caused by running and older version of the app, other auto-ID sensors will work with your LabQuest. To get the latest version of the LabQuest software, see https://www.vernier.com/downloads/

C. The issue is with the sensor and not the LabQuest
Connect the sensor to several different LabQuest units. If the sensor does not ID in any LabQuest (and you have ruled out A and B above), then the issue may be with the sensor and not the LabQuest. If that is the case, contact Vernier Tech support for further assistance.

D. The issue pertains only to a some LabQuest channels
Try the sensor in all of the channels of the suspect LabQuest. If the sensor works in some, but not all, channels of the same LabQuest, you will need to contact Vernier Tech Support for further assistance.

If you have eliminated the possible issues noted above and are still having trouble, try the following steps to address the issue:

1. Cycle the power and/or reboot your LabQuest
LabQuest 2 or LabQuest 3
Press and release the power button to turn the unit off, and then press the power button to turn the unit back on. If cycling the power does not work, try rebooting the LabQuest.
• LabQuest 2—Tap Home > System > Reboot
• LabQuest 3—Tap Settings > Reboot

Original LabQuest
Press and hold the power button down for 3 seconds, waiting until the power LED turns off. Then press the power button to turn the unit back on. If cycling power does not work, try rebooting the LabQuest. See How do I reboot or reset an original LabQuest?

2. If cycling power/reboot does not work, try this:
From the Meter screen, choose Sensor Setup from the Sensors menu. Verify that the channels are listed (CH1, CH2, etc.). If you see “no devices found” or the only thing listed are internal sensors, it may be that the data acquisition software is not properly installed.

To address this, apply an update to the unit. If you are already running the latest version, you can reapply the update. To update your LabQuest, go to https://www.vernier.com/downloads/

If you continue to have trouble, contact Vernier Tech Support for further troubleshooting.

See also:
Digital sensor does not automatically identify when connected to LabQuest after using the DCU.
LabQuest shows that a sensor is connected, but nothing is connected to that channel.
LabQuest App Sensor Setup doesn't list any channels