Intermittent display on Pioneer DEH-P7800MP car audio
Do you have an intermittent display problem with your Pioneer DEH-P7800MP car audio? Mostly this is because the flexible cable has worn out. See the picture below.
This tip will show you how to replace this cable.
Use a flat screwdriver to pry up the top cover. There are no screws attached.
Unscrew the four screws to take out the CD mechanism.
If the faceplate is not on ejected position, apply a 5V to the motor (shown on Figure 4) to stretch out the faceplate.
Unlock the connector on the main board, take out the broken cable.
Here are the new cable and the faceplate connector. If your old connector is good, unsolder it from the broken cable. You don’t need to replace it with a new one.
Peel off the adhesive liner, adhere and solder the connector on the cable following by the guide holes. (Figure 
Peel off another adhesive liner and adhere the cable on the metal plate.
Now put everything back and test the unit.
Where to get the flexible cable? Check the links below:
http://www.partstore.com/Part/Pioneer+Electronics/Pioneer/XNP7026/New.aspx
http://parts.pioneerelectronics.com/part.asp?productNum=XNP7026
http://www.encompassparts.com/products/?XNP7026
or check on eBay.