2023 Rivian R1T Visibility & Wipers Problems

On multiple occasions I have experienced the defrost feature of my 2023 Rivian R1T blowing cool air instead of warm or hot air, leading to a build up of ice on the windshield while driving. I have brought this concern to Rivian's attention with two service appointments, both of which resulted in Rivian noting they couldn't see any errors in the vehicle's diagnostic logs. I specifically noted the date, time, and temperature of one event but Rivian failed to copy the log data when requested. The issue is trivially reproducible in temperatures around 32ºF, when the defrost mode is enabled. Tapping the defrost/defog button on screen twice to enable defrost mode results in the vehicle selecting the vents for floor and windshield heat, speeds the fan to near maximum, and is supposed to blow hot air to aid in clearing built up ice. Instead what happens is the vents blow cool air for several minutes at maximum fan speed. Then the fan motors slow to their slowest speed at which time the vents blow slightly warm air After 5-10 minutes the fans speed up to maximum and the air coming from the vents is cool. When the vehicle was initially purchased, the defrost feature blew air hot enough to nearly be uncomfortable on the face. This is very much in line with any other vehicle I have owned when the defrost temperature and fan speed was set the maximum. But after an end of year update in 2024 or early 2025, the defrost feature began blowing cooler air and has never regained its original ability to clear the windscreen. The winter of 2025 and early 2026 has now resulted in this complaint. Rivian maintains the system is functioning as expected, but the service center staff doesn't quite seem to understand the severity of the issue. They claim a bug report can not be filed with Rivian until they capture an error in diagnostic data that they repeatedly fail to collect. Instead their advice is to enable cabin vents to warm the cabin instead of the windshield.