From memory as the 5xx series is alot of printers. Check the inkcart holder at the "parking station" where it rests( if that model has it). See if a small plastic lever is broken or loose or even fallen off. If broken only a replacement is a fix. Further, you can use water to clean the "timing fence/strip" but you can use Windex or similar just as good. You can also, with deft care, remove the strip as the spring is detented to be loose to more directly clean, use alcohol to clean using clean cloth. I found the strip reader really usually not at fault, actually trying to clean too well may loosen any crud and cause a problem. If it is the problem, its best to disassemble the carriage assy. to flush it out. Also a real good cleaning of the carriage slide bar and direct cleaning of bearing to remove dust crud build-up and or any old grease is a must, use light oil to relube or the special 3M printer grease(pink).
Those of you familiar with the HP DeskJet 500 series (500, 510, 520) will know that they are one of the best workhorses that HP ever made. I am trying to reclaim 5 old ones and have had trouble with 2 of them.
When switched on, the cartridge goes fully to the left and you get a loud sound, like crashing a car gearbox, then it halts. I have gently cleaned the whole length of the transparent reader ribbon - with water only - this usually works but not in this case. I have been told to clean the reader head inside the housing that the ribbon passes through. So... two questions...
1. How do I get at it to clean it.
2. If this doesn't work, what else could be wrong.

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