Search Forum Home   Inkjet Refilling  Troubleshooting  HP 78 cartridge...  HP 78 cartridge    9/18/2007 11:21:02 AM 48chev 1 posts HP 78 cartridge Hello, I have an hp c6578d cartridge that doesn't print, I've tried it in several hp printers. I took it to Walgreen's inkstation for refilling. Their initial test was an electrical test which the 78 failed. They cleaned the contacts and tried again-still failed. Does the 78 have internal circuitry? Can I check the contacts using ohmmeter and voltmeter? Are there details and specifics to help me? I've refilled the cartridge following Universal's instructions and using their inks. Could the electronics be damaged in the refill process? Thanks, Larry  5/7/2008 1:29:14 PM InkGirl 5 posts Re: HP 78 cartridge There isn't anything for you to check.  The electronics are on the cartridge (it's the bronze area).  Once the electronics fail there is nothing you can do to fix them.  You simply have to buy a new cartridge and start over.  There are many reasons why electronics on a cartridge will stop working: 1. Touching them with your fingers, the oils from our fingers will actually cause the electronics to stop working if touched to much. 2. Alcohol was put on the electronics; many people think alcohol is the best thing to use to clean the electronics and print head...majorly wrong answer, NEVER use alcohol, it will strip the protective coating off the cartridge and cause it not to work. 3. The electronics were hit by something (against another cartridge in a bag, or on something else, etc.) and 4. They simply stoped working.  Just like anything else electronic it can go bad at any point.  I have seen brand new cartridges not work becaues the electronics went bad.  So, as I said before, if the electronics aren't working, simply buy a new cartridge and toss the bad one. M  Page 1 of 1   Inkjet Refilling  Troubleshooting  HP 78 cartridge... Flat View Tree View Oldest To Newest Newest To Oldest