I have two DMR-ES35V combo recorder models that were purchased as parts machines. After initially powering on one of these with the remote or the front panel power button the machine displays the U61 error and will no longer respond to the remote or any front panel buttons. (The front panel circuit board contacts and left and right chassis motherboard contacts are correctly aligned.) This machine will briefly continue in the U61 state and then power itself off after which it will remain unresponsive until disconnected from the power for a time and then reconnected. The U61 will reappear following powering on. The DVD drive has been swapped with another known good DVD drive from the other DMR-ES35V parts machine. The DVD drive controller circuit board has also been swapped with that from the other parts machine. (The other parts machine had a defective tuner but did not report the U61 error.) Note: many parts may be interchanged between several models from the same model year, but not between models from different model years. (All the models mentioned in this post are from the 2006 model year.) This DVD drive controller circuit board carries the machine's main CPU, the RAM, and other major chips. The U61 error persists on this machine. There is some evidence of leakage from the largest electrolytic capacitor (C11108) in the power supply section.
I have three other functional DMR-ES35V models that also evidence leakage from this same power supply capacitor. I have temporarily removed these three machines from service pending replacement of these capacitors. (These three functional machines average more than 3,000 recording hours per machine.) I expect to replace these leaking capacitors in all four machines at the same time, a procedure that requires disassembly to the extent of removal of the right chassis motherboard from the machine. Due to the extensive disassembly required the procedure takes somewhat longer than one hour per machine.
I have another functional DMR-ES35V that does not exhibit leakage from this electrolytic capacitor. That machine continues in daily service. I also have four DMR-ES15 models, where, in three of these I replaced the similar largest power supply section electrolytic capacitor (C1143). Two of those three are in current daily service.
I have previously posted detailed instructions for replacement of the power supply electrolytic capacitor on a hard drive model here:
Those detailed instructions are generally the same for Panasonic DVD recorders and combo recorders. Combo recorders have left and right chassis motherboards with conductive bridges/connectors between the motherboards. On a combo recorder be sure to hold the VHS door open when fitting the front panel back to the case. This will assure the correct alignment of the VHS door lifting mechanism.
Replacement of leaking electrolytic capacitors may or may not correct the U61 error. If not, then I suspect the most likely cause is some failure of a component on the DVD drive controller circuit board.
The corporate Panasonic Service Center is located in Elk Grove Village IL. They offer the $130 flat-rate repair that includes shipping both ways. Usually Panasonic factory refurbished DMR-ES15 models, with a 90 day Panasonic warranty, are offered by Panasonic Authorized Resellers on eBay or other online locations under $70, plus shipping.