Hybrid control unit

[snwyrvr]

I have a 2008 rx 400h with 225,000 miles on it. I was getting Maintenance Required light off and on for a month and had planned to take it in but this week there was also a message to check hybrid system. That went away after a day and the maintenance light came back solidly. I took it in to my repair shop today and they put 3 code readers on it but can’t solve the issue. The read out is U0009 and they think it might need a hybrid control unit and they told me to take it to the dealer for a better reading. Have any of you experienced this? And does the replacement unit have to be programmed by the dealer or can my repair shop do it. Thank you. 

[RX400h]

I once had a similar warning so I checked the battery and found one cell's water level lower than the others. So I added distilled water, charged the battery and never saw the message again.  That was 4 years ago. The maintenance required light is typically set to come on, 5000 miles after the last oil change.