Since upgrading to iOS 26, my iPhone 15 Pro (A17 Pro) exhibits persistent battery drain and thermal issues. Console.app analysis via Mac reveals a cluster of related kernel and daemon errors that appear to stem from a driver-level regression rather than a hardware fault. Observed errors (continuous, since boot): thermalmonitord fails to read the cpu-avg-limiter-input-w2r property every 5 seconds indefinitely. This leaves the thermal throttling subsystem unable to regulate CPU load using its primary input sensor. The kernel logs SPMI bus faults on nub-spmi1 at a perfectly regular 30-second interval (codes 0x72040C01, 0x75E40C3B, 0x72D80C33), alongside aop-spmi0 faults (0x7A000830). The strict periodicity strongly suggests a driver retry loop rather than a dead hardware component. appleh16camerad (ISP driver) fails to initialize endpoint 1 (fISPEndpoints[1] is not ready) and retries every ~4 seconds, while the ANE driver (ANE0) cannot register its memory unwire timer. Both run in permanent retry loops consuming CPU cycles. AppleSMCFamily logs kSMCKeyNotWritable errors on SMC write attempts — the key exists but is flagged non-writable, suggesting incomplete driver initialization rather than a missing component. A single AppleSARService coredump request for the baseband was also observed. Why this appears to be a driver issue and not hardware: The system remains stable with no kernel panics or forced reboots. The SPMI faults occur on a precise 30-second schedule consistent with a kernel timer, not random hardware failures. The SMC error is kSMCKeyNotWritable (key present, wrong state) rather than kSMCKeyNotFound. All symptoms appeared immediately after the iOS 26 update with no physical event on the device. Device: iPhone 15 Pro — A17 Pro iOS version: 26.0 Reproduced: persistent across reboots, not tied to any specific app or usage pattern Has anyone observed the same pattern on A17 Pro devices? And has Apple acknowledged any SPMI / thermalmonitord regression in iOS 26 for this chip family?