Neff C67M70N0GB-09 fault code error E300 - How to fix it?

[mariukonie]

Neff C67M70N0GB-09. After a power grid failure, when the operator turned the power back on, there was some overload, because the oven shows error E300 and nothing can be done, even the clock cannot be set. From what I knew, the operating module (the one with LCD displays) was damaged. Can anyone advise how to fix this? A new module is very expensive, so I would rather repair the one I have. Thanks in advance for your advice .

[CapLeaker]

I suggest you post some straight shot, high resolution pictures from front and back of the board, so we can see something.

[mariukonie]

Thanks. Please ignore some bad looking solders as I was already trying to diagnose it a little bit.

[CapLeaker]

You do have to fix your soldering. I am guessing so far same thing. It couldn’t have been the caps, since it is saying E300 and isn’t completely dead or something. But there are individual voltage regulators, protection diodes and regular diodes and transistors. Is there a sort of paper schematic the oven came with? Should be in a pouch somewhere on the back of the oven.

[mariukonie]

I know my soldering is bad, I'm working on it I don't have sny schematics unfortunately but the orange cables are the ones that come in from main control pcb so they are supplying module with power hence I would guess that's where surge of power would come in What would be the most likely culprit? All black cables go to control knobs on the front panel.

[CapLeaker]

Some are doing some sort of reset. Look at this: https://www.youtube.com/watch?v=u5Pv2ucxdxE
From what I also gathered, it has something to do with the firmware. If you can't do that reset apparently the firmware is bad.

Here another snippet I found:
Error E300 occurs due to inconsistency between the instructions of the control board and the module with the software. In other words, this is an electronic unit error.
It is difficult to find detailed information about this error on the Internet, because to eliminate it you will need to get into the “electronic brain” of the oven and make some changes.
The problem can have two solutions:

1. Partial change in the program code (with the error constantly blinking).
2. Complete code update (if the error is static).

If you encounter such a malfunction, we will help you fix it. Most often, the technician will perform the work of reprogramming the module at home, with rare exceptions - at a service center.


Now how they flash that thing and with what I got no idea.

Here is something out of the manual:
The temperature display shows, “EXXX”,
e.g. E300
Internal fault in the appliance electronics Press the .- clock function button. If the
message does not go out, pull out the
mains plug and plug it back in again after
approx. 10 seconds

[mariukonie]

Thanks. E300 on mine is static, I did put it into test mode as shown in video and it was testing everything fine but there are some settings that I don't know what they mean, Should I just try different settings on a hit and miss basis?
Pressing clock button and unplugging for 10 seconds also didn';t help.

[CapLeaker]

Maybe take some more pics. In any case it doesn’t look good if you need to have your firmware flashed.

[redbomb65]

hi,
i did some research, in my simens service programm, and found: e300 1. wrong modul kombination {screen <--> control pcb} 2. wrong variant code.
what i read you can programm or change the code. You need access to the testing program in the device. Then the type plate is still required. Then a number must be converted into a hexadecimal number and then changed on the electronics. then the device should work again. Unfortunately, there is no PC access (i-service) on the device. This means that if this doesn't work, one or both electronics may need to be replaced. because the program is permanently stored on the ICs.

[sam_sam_sam]

I am NOT impressed with this controller board at all for it to go into an error message that is not recoverable what nonsense is this crap this almost as bad as what Whirlpool did few years back with some of controller boards on some of their refrigerators the only thing you could do was replace the controller board

Other manufacturers have done this from to time make devices that there is no way to repair them without going through the manufacturer this more crap this nonsense even done with industrial equipment as well and just want to strangle the people who do this crap

And what is worse is not to offer a solution for the problem with controller and you search far and wide to maybe find a solution to the issue at hand REALLY I would never knowingly buy a product that controls your life that way

[CapLeaker]

hi,
i did some research, in my simens service programm, and found: e300 1. wrong modul kombination {screen <--> control pcb} 2. wrong variant code.
what i read you can programm or change the code. You need access to the testing program in the device. Then the type plate is still required. Then a number must be converted into a hexadecimal number and then changed on the electronics. then the device should work again. Unfortunately, there is no PC access (i-service) on the device. This means that if this doesn't work, one or both electronics may need to be replaced. because the program is permanently stored on the ICs.

Yeah I did look for some test points on the board and didn’t find any. Not saying there aren’t any… However maybe the chip can be taken off and reprogrammed / replaced.
So you take the type plate, convert certain numbers to hex and insert these somehow in service mode? Interesting. I couldn’t read the part number of the IC so not sure what it is.

[redbomb65]

i will post a part of the service manual. but its only in german. google tanslator will help

[CapLeaker]

i will post a part of the service manual. but its only in german. google tanslator will help

no problem, post the german service manual.

[lotas]

I couldn't read the part number of the IC so not sure what it is.

Microcontrollers used here are from Renesas.