I hope this post gets on the forum---I tried updating yesterday, but somehow my entry does not appear in this thread...
After damaging an InkJetMall refillable cart for our 3800 printers, I filled and installed the new #7 (LC) cartridge with Piezo-Flow, and inserted it in our 3800 #1. The printer refused to recognize the cart, as well as #'s 8 (LM) and 9 (Y). MANY attempts produce the same result. I even followed the instructions for re-setting the printer---unlock all 9 carts, slide out waste ink tank, turn off printer for more than 3 minutes, turn printer on, slide in the tank, close its door, insert carts in numerical order, close cart bay door. Didn't help, tried multiple times.
I was worried that a leaking LC cart had spread PF inside the printer last week, possibly affecting the electronics or other critical parts. So I removed carts 7,8, and 9, and replaced them with Original Equipment Manufacturer's (Epson) carts. Bingo, all carts were accepted, so did a few nozzle checks, then a test print to confirm. Because 6 of the 9 carts are flush carts, the print was kind of pink-y, but otherwise fine. The printer seems to work well, disproving the possibility that 3800 #1 was damaged by the leak.
Then, I took the entire set of IJM carts to our 3800 #2. Once again, carts 7,8, and 9 were not recognized. While I was lifting the bottom edge of the installed carts, as the instructions direct, I noticed that when lifting the yellow / #9 cart, ALL the carts were suddenly recognized. Firm upward pressure is required---as soon as I reduced the pressure, all the cart positions flashed, unrecognized. So I cut a piece of some firm foam packing material and stuffed it under cart 9. All carts were then recognized, and I successfully ran a power cleaning to push PF into the lines and head. Waited a few minutes, as Dana suggests, to avoid over-taxing the head, and then repeated. When the 2nd cleaning was completed, I ran a manual nozzle check, and found that some ink still remains in the head, though diluted. Did another power-cleaning, and retested: all remnants of color gone. Success! Then, changed from Photo to Matte black ink, and repeated the series of three power-cleans to flush the Matte channel.
I then took the set of IJM flush-carts to 3800 #1 and finally had success here the same way: I had to wedge something underneath the Y cart to hold it tight against its contacts. Only that cart required this treatment---in two different 3800's--- so I'm wondering if it may be defective.
The lesson here seems to be that a single cart that is not seating well against its chip-reading contacts may cause all the others to not be recognized.
Dana, I hope you see this. I'm puzzled why my posts seem not always to make it to the forum.