Searching didn't seem to turn up this info, so I'm wondering if anybody knows where the temperature sensor is located in a TiVo HD unit.
When I woke up 6/21 the TiVo was endlessly rebooting. The temperature in the room was a few degrees higher than usual, so I lowered the room temperature and the TiVo agreed to start working again. It continued to work fine all day and night. The room temperature was allowed to rise a few degrees again overnight, and this morning the TiVo was failing again. Lowering the room temperature just a few degrees again got it out of its rebooting loop.
The TiVo is reporting an internal temperature 6-8 C higher than usual. Normally the temperature is 36-38 C, but now it's 44-45 C once it warms up. It seems to start rebooting once it goes over 46 C.
Cleaning out what little dust was inside made no difference. I already clean it at least twice a year with an ESD-safe vacuum. I also already had two extra fans in the unit (a small one on the heatsink on the motherboard, and a second 60mm fan in the front of the power supply since there are vent/intake holes there). The hard drive isn't the problem, it has been checked. There are no obviously bad capacitors on the power supply.
While I suspect the power supply is probably responsible for this situation, I am very suspicious of the increase in the detected internal temperature and would like to investigate it further. There's no way the air inside of the case should be 6-8 C higher than usual, so I'm guessing the sensor is failing, or something is running much hotter than usual, or maybe the heatsink on the motherboard isn't making good thermal contact anymore. If something specific is getting too hot, it's probably near the sensor since everything inside that I consider safe to touch while the TiVo is running feels normal.
Any help would be appreciated before I seriously consider tracking down a replacement power supply.