iR6870 On/OFF by itself

[Alan Aya]

Hi guys,
I am having this problem with my iR6870C, when the machine is in ready stage, suddenly the machine OFF & ON by itself, it starts warming up, initial rotation until it comes to Ready. But after a while,it OFF & ON again and again,
Any idea of solution for the problem.
Thanks

[mrfixit51]

Is it posting any error codes when this occurs?? Have you metered the line voltage during this off/on cycle?

[Guest]

Hi guys,
I am having this problem with my iR6870C, when the machine is in ready stage, suddenly the machine OFF & ON by itself, it starts warming up, initial rotation until it comes to Ready. But after a while,it OFF & ON again and again,
Any idea of solution for the problem.
Thanks

Check the thermal switch, check the heater lamps.
When was the last time the fuser unit was rebuilt? Make sure that the thermal switch is making contact to the upper fixing roller. When the machine starts to do its initial rotation, AC is applied to primarys, transfer rollers and most important AC is applied to those lamps. If they don't fluctuate on and off which this is the thermal switch job, to detect and determine when the lamps should turn on or off along with the thermistors. If the thermal switch is off or barely making contact, the lamps will over heat plus blow out PCBS. This is one reason a machine like this will shut off when the machine shuts off like this you will not get any error codes, it just shuts off.

[20YRSEXP]

I would also check the line voltage and if it has a surge protector you might want to try another one. Go into service mode and check for error codes and alarms that may have been listed in the history.

[Alan Aya]

Check the thermal switch, check the heater lamps.
When was the last time the fuser unit was rebuilt? Make sure that the thermal switch is making contact to the upper fixing roller. When the machine starts to do its initial rotation, AC is applied to primarys, transfer rollers and most important AC is applied to those lamps. If they don't fluctuate on and off which this is the thermal switch job, to detect and determine when the lamps should turn on or off along with the thermistors. If the thermal switch is off or barely making contact, the lamps will over heat plus blow out PCBS. This is one reason a machine like this will shut off when the machine shuts off like this you will not get any error codes, it just shuts off.

Checked thermal switch, thermistor, heater lamps and even exchange the whole heater unit but the problems still coming back.There is another symthom, sometimes in ready stage, the operation panel including the number keypad is locked, it hanged. I did replaced the HDD, Memory & the BootROM but still doing no good. Any ideas?

[20YRSEXP]

You said it goes thru warm up? Did you watch the temperature in service mode? Did you check the outlet? does it have a surge protector? If the panel is locking up maybe the problem is in there(but it is probably just a symptom).
When you check the outlet check for proper voltage and a good ground. Also make sure it is the proper configuration. Has the machine been at this spot for a while? If so you would probably think the outlet is good, but I have seen a good outlet go bad because the did work on the electrical system and changed the outlet configuration at the cicuit board.

[20YRSEXP]

A complete shutdown could indicate a pinched wire, but that could be a tough thing to find. I hope it's not that.

[hachetman]

Hi guys,
I am having this problem with my iR6870C, when the machine is in ready stage, suddenly the machine OFF & ON by itself, it starts warming up, initial rotation until it comes to Ready. But after a while,it OFF & ON again and again,
Any idea of solution for the problem.
Thanks

Sounds like your fuser is over heating canon copiers will shut them self of if they reach to high of temp try replaceing th1 & th2 !

[20YRSEXP]

Thats true Hatchet, but they would not turn themselves on again. There would be an error in history and you would have to clear the code for it to start up. This is starting up by itself after the shutdown. This sounds like a power issue and for that matter you might think a new power supply. Not the first thing I would jump to, but I wouldn't rule it out.

[Guest]

Thats true Hatchet, but they would not turn themselves on again. There would be an error in history and you would have to clear the code for it to start up. This is starting up by itself after the shutdown. This sounds like a power issue and for that matter you might think a new power supply. Not the first thing I would jump to, but I wouldn't rule it out.

20years is correct about the power supply and or the relay. As I was reading the post and read and saw that the fuser unit was completely swapped and the machine still shuts down!

This indicates that there is a power issue, plus the freezing up could relate to a power issue as well. Hit the books check the schematics, check voltage.

[Alan Aya]

20years is correct about the power supply and or the relay. As I was reading the post and read and saw that the fuser unit was completely swapped and the machine still shuts down!

This indicates that there is a power issue, plus the freezing up could relate to a power issue as well. Hit the books check the schematics, check voltage.

Thanks for the info, but the machine is still giving the same problem, i even change the PSU (including the relay & board), DC controller,AC driver PCB. The voltage is consistent.Problem still not corrected, service manual i am having now without the schematics daigram, help from you guys is much appreciated.

Thanks

[Guest]

What about your drum heater?

[20YRSEXP]

Was there any work done on the machine prior to the problem? Maybe it is something someone did. If it is a pinched wire, tracing back were people have been working is a good place to start. Also, depending on how frequent this is, you might find something by pulling out the drawers and wait to see if it happens. If it happens while drawers are out you can at least eliminate them as the problem. And does it happen at the same time or does it seem random. Pay close attention and you might find something. Any more details you can think of might help.

[rad7845]

we had one that would power off turned out to be the drum heater.