CP4025 Continuous Calibration

[Big Al]

We got five of these back from a deployment. Four worked fine. One goes through POST, Initializes, then starts Calibration. For about two minutes it runs the engine then settles down to continuously showing CALIBRATION. The others all took just about two minutes to go to READY. This one just sits there. If you push the CHECK button and ask it to do something, like print a status page, it will run the engine briefly then go right back to CALIBRATION again and sit there for an hour. I downloaded the service manual. It suggested an NVRAM reset. We did that and it seemed to go well but had no effect on the constant calibration. We swaped all the cartridges with another working unit and this had no effect either. The other printer calibrated just fine with the bad printer's cartridges. I reseated the formatter, there was no DIMM, but this did nothing as well. It is about five months past warranty. I found a post on Google where someone had this problem with an HP 3600 and the NVRAM reset fixed it. Any ideas anyone?

Thanks, Al

PS: Sorry for all the blather! I swapped the formatter and this thing came READY. I put the origional formatter back in and now all is well! Since Data Processing is a branch of Electronics, and Electronics is not an exact science, I have no explanation for this one! Al

[ridered74]

We got five of these back from a deployment. Four worked fine. One goes through POST, Initializes, then starts Calibration. For about two minutes it runs the engine then settles down to continuously showing CALIBRATION. The others all took just about two minutes to go to READY. This one just sits there. If you push the CHECK button and ask it to do something, like print a status page, it will run the engine briefly then go right back to CALIBRATION again and sit there for an hour. I downloaded the service manual. It suggested an NVRAM reset. We did that and it seemed to go well but had no effect on the constant calibration. We swaped all the cartridges with another working unit and this had no effect either. The other printer calibrated just fine with the bad printer's cartridges. I reseated the formatter, there was no DIMM, but this did nothing as well. It is about five months past warranty. I found a post on Google where someone had this problem with an HP 3600 and the NVRAM reset fixed it. Any ideas anyone?

Thanks, Al

PS: Sorry for all the blather! I swapped the formatter and this thing came READY. I put the origional formatter back in and now all is well! Since Data Processing is a branch of Electronics, and Electronics is not an exact science, I have no explanation for this one! Al

I have an explanation, tho I'm not sure that it is correct. I've had that issue with 3600/3800 models twice in the past. The first time I was able to swap cartridges and the problem went away. The second time I fixed it with a firmware uprade. As I was reading your post I was leaing towards suggesting firmware until I got to the part where you fixed it.

On the cp4025 the firmware is stored on both the formatter and the dc controller. My hunch is that when you put the different formatter in, the firmware from that formatter was transferred to the dc controller thus un-flaking the electronics in it. Not sure that's what happened, but that's my only explanation.