Modern smartphones use a standard called to communicate with the cellular modem. Within this system, network types are assigned integer numbers (codes) so the processor knows which protocol to use.
| Cause | Explanation | |-------|-------------| | | Modem reports invalid enum due to a race condition or uninitialized variable | | Incorrect RIL implementation | Custom RIL daemon sends wrong value for a new network feature | | Logging error | Debug code prints raw integer without validating against known types | | OEM extension clash | Vendor uses 276 internally (e.g., for testing or emergency mode), but AOSP RIL doesn’t recognize it | | Corrupted NV item | Non-volatile memory storing network preference gets corrupted | network type 276 unknown or unsupported
If none of the above works, the issue may lie with your SIM card hardware. In that case, visiting your carrier’s store for a SIM swap is the final step. Modern smartphones use a standard called to communicate
Examine diag logs for the exact message causing the 276 value. In that case, visiting your carrier’s store for
A hardware manufacturer has assigned "276" to a proprietary communication method.
network type 276 unknown or unsupported is generally a caused by a mismatch between modem firmware and RIL expectations. It rarely affects call/data functionality, but indicates a need for enum validation in the radio stack. If accompanied by registration failures, investigate modem state or carrier network mismatches.
adb shell echo 1 > /sys/kernel/debug/msm_subsys/modem