It seems from earlier posts you are familiar with all the technical details of Pioneer TVGOS recorders, so I'll assume you already tried the various resets and whatnot that sometimes restore TVGOS after a random malfunction. If so, most likely your problem is the TVGOS signal has been dropped in your area. It vanished from off-air broadcasts when we made the switch to DTV, and has slowly been dumped by one cable system after another as they shift towards digital QAM. Its kind of a hassle for them to jump thru the hoops of analog>digital>analog TVGOS conversion and patching it back in to the host channels, and they have no real incentive to do it, so its been phased out in many areas.
You could put a call in to your cable customer service office to request they turn TVGOS back on, but the process of getting thru to someone who even knows what you're talking about is difficult. You might want to look at the AVS Panasonic TVGOS recorder threads for detailed info on how to speak to your cable reps on this topic. Most Pioneer TVGOS recorder owners gave up on their machines long ago due to breakdowns and other issues, but the Panasonic owners are like rabid dogs whose bone is being threatened: they really keep the pressure on to extend TVGOS service as long as possible. You want help with your TVGOS service, you need to talk to a Panasonic owner.
If it turns out the pilot signal is no longer available to you, its probably a good idea to deactivate the TVGOS feature and use your Pioneer under full manual timer control (to avoid the endless EPG alert on the front panel causing random operational problems). In case you haven't already bookmarked the procedure, here it is again (courtesy AVS member Sean Nelson):
IF THE TVGOS SIGNAL HAS SIMPLY STOPPED IN YOUR BROADCAST AREA, AND YOUR PIONEER 531, 533 or 633 IS OTHERWISE WORKING NORMALLY:
All you need to do is tell the recorder that TVGOS service is gone and it needs to stop trying to use it. This can be a little tricky, because the recorder is engineered around the fundamental assumption that it will always have a TVGOS signal to rely on. This is the number one problem with the 531-533-633: they cannot let go of TVGOS, even when you turn it "off" you have to remain vigilant against the machine over-ruling your instructions and reactivating TVGOS on its own, usually in the middle of the night while you're asleep. When the Pioneer TVGOS cannot find a pilot signal, it grinds the hard drive relentlessly until it corrupts itself and becomes one huge headache to deal with. This is what you must do to prevent that:
1. Do a hard reset of the recorder: turn it on, wait for the "Please Wait" alert to go away, then hold down the "STOP REC" button on the front panel. While holding down "STOP REC", press the "STANDBY/POWER" button and hold both buttons until the recorder shuts down. If it does not restart by itself, wait five minutes and then turn it back on.
2. The recorder will have cleared all of its settings and should present you with the initial settings menu for the clock, etc. If it does not, press the Home Menu key on the remote and select the onscreen Initial Setup button. Enter all the setup information (date, time, etc.). At some point in this process the setup screen for TVGOS should appear- if it does not, press the Home button on your remote and select the onscreen TV Guide button. With the opening TV Guide Setup screen showing (the one with a picture of a television on the left), press the remote's enter button to begin setup.
6. Choose "Canada" as your location.
7. Set Postal Code to A 0(Zero) A 0(Zero) A 0(Zero)
8. Choose Cable
9. Choose No Cable Box
10. Confirm Settings OK and exit.
11. Immediately go back into TVGOS Setup and repeat steps 6 thru 10 a second time, to be sure your choices "stick".
12. Press the Timer Rec button on the remote and set a recurring manual timer entry: you MUST do this to lock TVGOS in manual mode, otherwise it will begin searching for a pilot signal the moment you power off the recorder. If you have a show you normally record every day or every week anyway, thats ideal, if you don't normally do this then just set a random odd time like 5:00am to 5:15am every Wednesday. Then just delete this "dummy" recording every week afterwards.
BTW, the manual timer setting screen takes some getting used to if you have previously only used the point-and-click automatic TVGOS timer grid. Some of the data entry fields (date, time, channel) are only set using the numeric keypad on the remote. Other fields (AM/PM, input, recording speed, once-daily-weekly) are set using the left and right arrow keys. You navigate up and down the entry fields using the up and down arrow keys.
13. You're done! TVGOS will stop spinning the HDD and stop searching for the now-gone TVGOS signal. When you want to set a timer recording, pressing the "timer rec" button will bring you directly into the manual timer screen. When you turn the recorder off, it will turn completely off. There should be no more alert displays due to TVGOS.