Tivo Power Supply Repair

I’ve got a very old Tivo, an HRI-250. Last week we had a major power outage that lasted 12 hours. When the power came back on, my Tivo did not. It had been having some over-heating problems, so I wasn’t surprised.

Investigating further, I found that I was missing some of the supply voltages. The Tivo supply provides 12V, 5V, 3.3V, and 32V I believe.

There were several capacitors that were puffed out on top – a sign of failure. So, I set out to replace those.

There were pairs of 470uF, 2200uF, and 3300uF caps that looked to be bad. I removed them in pairs and tested them. All of them measured very high ESRs and low capacitance.

I ordered replacements through my primary electronics parts dealer, Amazon.com and they arrived the next day.

Hopefully the replacement capacitors are able to withstand the high frequencies in the switching power supply. If not, I’ll have to order more specialized caps from Digi-Key.

Here are some photos of the repair. I had to remove the heat sink with power transistors and diodes attached in order to remove the caps. They caps were fixed to the board with a nonconductive fixating compound which I left alone as much as possible.

So far the Tivo is working great and running cool at 39C


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