bizhub 458e Fusing temperature control

[REGSIS]

Hello!

Problems started with C3736 (hi temp) error. After reset machine worked half a day and showed C3825 (low temp).
After that C3726 and C3736 showed after each job.

Anyway, trouble can be reset every time, warmup does complete, print job executed no matter of number of pages tens or hundreds, but after print job is finished - few second after (cool-down) temperature should lower to standby predetermined
value but it doesn't apparently - error is shown.

Machine has only 80k, fuser looks like new, I disassemble it and checked thermistors (1 central and 2 on edge) - everything clean and without paper pieces or any other foreign objects inside it.
Since I hadn't fuser failure at low counter like this I suspect at Fuser power supply board (FUPU) malfunction. This board is also present in C458.
Higher models 558e/658e and C558/C658 have IHPU board instead.

Did anyone had such symptoms that are board related (or something else other than fuser).

P.S. If I get always the same error I would suspect that is thermistor related, but they couldn't be all 3 at fault at once. I'm afraid that fuser replacement would not solve the problem.
It's a pity that I don't have any other machine in the field to test the fuser (or FUPU) on it.

[tsbservice]

I feel your pain brother. I was in same situation I needed to replace bad fuser on our only one 458e. Friend of mine gave me a fuser looking almost brand new but he didn't know if it works. So I went and do some testing on another 458e(not mine). I did quick 50+ pages test on fuser and it was fine, what was my surprise when replaced bad fuser and after few hundred pages it coded thermistor error (can't remember exact number). So I have to wait for new fuser to arrive and change bad one. My point is you really should borrow another known good fuser and test it before going for boards. In any case good luck 🤞

[allan]

@tsbservice is dead right there. Get another fuser to test first of all. Then move it to a plug point on another breaker circuit.

All the fuser settings under Service mode -machine set to default? Try mode 4 under system 1 Warm up. Don't think any of that would help but its things to try.

If the AC from the wall fluctuates the DCPU has state of the art switch mode technology that will keep the DC even, even with voltage variances +/-50V AC! The power supplies on these are unbelievable.

The FUPU gets instruction to switch the 3 lamps on or off and get its AC power directly from the mains and power dips here will affect the fusing performance in a big way. Its the muscle end of the control and generates noise so it needs to be isolated from the SMPS's(PSU's) and the MCU's(MFPB). The FUPU also send the ZEROCROSS sync to the MFPB.

But the MFPB is at the heart of the control.

CN2E on the MFPB is the control output to the FUPU.
CN12E on the MFPB is the control input from the sensors on the fuser.


I will start will a power logger between the wall socket and the machine if another fuser does the same.

[REGSIS]

IIRC I didn't hear a fan that should turn ON and lower the temperature after print. That crossed my mind when I left the site.
An error code for fan was never shown.
That should be the exaust fan on top or right-side door, am I right!

There's no other 458e machine in my county to test the fuser or FUPU.
I can only test the fan if it's same as the one inside C558.

[copier tech]

Hello!

Problems started with C3736 (hi temp) error. After reset machine worked half a day and showed C3825 (low temp).
After that C3726 and C3736 showed after each job.

Anyway, trouble can be reset every time, warmup does complete, print job executed no matter of number of pages tens or hundreds, but after print job is finished - few second after (cool-down) temperature should lower to standby predetermined
value but it doesn't apparently - error is shown.

Machine has only 80k, fuser looks like new, I disassemble it and checked thermistors (1 central and 2 on edge) - everything clean and without paper pieces or any other foreign objects inside it.
Since I hadn't fuser failure at low counter like this I suspect at Fuser power supply board (FUPU) malfunction. This board is also present in C458.
Higher models 558e/658e and C558/C658 have IHPU board instead.

Did anyone had such symptoms that are board related (or something else other than fuser).

P.S. If I get always the same error I would suspect that is thermistor related, but they couldn't be all 3 at fault at once. I'm afraid that fuser replacement would not solve the problem.
It's a pity that I don't have any other machine in the field to test the fuser (or FUPU) on it.

You maybe going in a bit deep here. I would simply fit a fuser first then go down the PSB route.

[REGSIS]

You maybe going in a bit deep here. I would simply fit a fuser first then go down the PSB route.

Yes, I was digging deep (just to be sure). This was fixed with a new fuser.
More different errors were shown as the time passed which led me to conclusion that something is wrong with a fuser lamp.

[tsbservice]

Those fusers are crap anyway barely making past half life before start to accumulate dirt on belt.

[Hansoon]

Those fusers are crap anyway barely making past half life before start to accumulate dirt on belt.

So the "8" series are not that good as announced here?
Have none of them yet, shall I better stay with the "4e" series?

Hans

[tsbservice]

So the "8" series are not that good as announced here?
Have none of them yet, shall I better stay with the "4e" series?

Hans

Hans, this is 458e mono machine with different fuser.
Fusers for C258-C368 machines are the same as for C224e-C364e.

[elmaligno]

Hello!

Problems started with C3736 (hi temp) error. After reset machine worked half a day and showed C3825 (low temp).
After that C3726 and C3736 showed after each job.

Anyway, trouble can be reset every time, warmup does complete, print job executed no matter of number of pages tens or hundreds, but after print job is finished - few second after (cool-down) temperature should lower to standby predetermined
value but it doesn't apparently - error is shown.

Machine has only 80k, fuser looks like new, I disassemble it and checked thermistors (1 central and 2 on edge) - everything clean and without paper pieces or any other foreign objects inside it.
Since I hadn't fuser failure at low counter like this I suspect at Fuser power supply board (FUPU) malfunction. This board is also present in C458.
Higher models 558e/658e and C558/C658 have IHPU board instead.

Did anyone had such symptoms that are board related (or something else other than fuser).

P.S. If I get always the same error I would suspect that is thermistor related, but they couldn't be all 3 at fault at once. I'm afraid that fuser replacement would not solve the problem.
It's a pity that I don't have any other machine in the field to test the fuser (or FUPU) on it.

I had several machines in that range with such codes and I always solved it by changing the fuser. And with not too many copies.