Hi Denis, Thank you for the quick response. By the way, I'm not able to post to ofono(a)ofono.org, so this reply probably won't show up there. I've not figured out what the problem is, but suspect it's blocking "garmin.com".

The issue is that Quectel has a single mode LTE modem that populates all 3 fields. They do this because they also have the same modem that only supports CDMA. So, the current oFono code returns the ESN even though my modem is LTE only. Your info below is very informative, thanks! The CDMA info also confirms my observation about its level of support. I have an alternative idea. What if I query QMI_DMS_GET_CAPS, figure out which radio_if is supported, then return IMEI if GSM/UMTS/LTE is supported, else ESN or MEID? This way Modem.Serial property will still behave as it does now.