I have a Hitachi EX120-2 with hydraulic problems.

[Diesel Dave]

Ok great what should I do next. I worked for John Deere for 6 years and I do this for living now so I am very familiar with electrical diagnosis. I have the factory shop manual on my laptop.

You can remove the PVC and remove the cover. IIRC there is a small internal component that gets fried. I don’t remember much more than that but there are threads here on HEF discussing it.

 

[dgvanpelt]

Outstanding thak you so much

 

[mg2361]

Just to clarify, you checked for voltage at pins 37, 39, and 46 on the bottom controller (PVC)? Did you make sure you have a good connection to ground at pins 38, 47, 101, and 109? If all this checks out, take the top cover plate off the PVC. Look for the the resistor shown below. Does it look burnt like in the picture? If you orient the blinking LED to the top right corner, the resistor will be in the bottom right corner, if I recall correctly.

 

[dgvanpelt]

All the grounds and hot pins check out. I took the cover off and found a burnt spot. I am forwarding a picture. So it definitely needs the PVC. Thanks for all your help.

 

[mg2361]

How is that white resistor?

 

[dgvanpelt]

That resistor is open.

 

[mg2361]

Is it burnt?

 

[dgvanpelt]

No it isn't

 

[dgvanpelt]

Thank you for all your help I am trying read the flashes from the PVC and there is long flashes and short flashes how exactly do i decipher them. Oh I replaced the PVC and now I get flashes when I short the two wires in diag plug

 

[mg2361]

there is long flashes and short flashes how exactly do i decipher them.

Check your messages.

 

[SILVADARIO]

Just to clarify, you checked for voltage at pins 37, 39, and 46 on the bottom controller (PVC)? Did you make sure you have a good connection to ground at pins 38, 47, 101, and 109? If all this checks out, take the top cover plate off the PVC. Look for the the resistor shown below. Does it look burnt like in the picture? If you orient the blinking LED to the top right corner, the resistor will be in the bottom right corner, if I recall correctly.


View attachment 324643

Hello, I'm new here. I have the same problem. I found the 10 ohm resistor burned out. I need help. If I just change the resistor, will it work?

 

[mg2361]

Welcome to HEF SILVADARIO!

There is most likely a short somewhere in the 5 volt reference circuit which is what burns the resistor. If fuse #7 has anything higher than a 1 amp fuse, then it will fry the new resistor when the short occurs.

 

[SILVADARIO]

novamente

Thank you very much for your attention. I will be checking again next week if there is any news I will return here. I really appreciate your help.

 

[SILVADARIO]

Hi, so a changed controller and 2 valve. I checked the error by the lights on the PCV led. The led show's 5, 22, 31(5 short, 2 long and 2 short, 3long and 1 short light)and search in web and manual but nothing. Anyone know what that error can mean? Thanks for listen.

 

[mg2361]

5-?
22- Pump control not normal
31- Disconnected temperature sensor or wiring issue to the sensor.

 

[Diesel Dave]

code #5, Signal from PVC is not transmitted to EC .

 

[SILVADARIO]

5-?
22- Controle da bomba não normal
31- Sensor de temperatura desconectado ou problema de fiação no sensor.

Muito obrigado. Vou ter que verificar novamente para descobrir as causas.

 

[SILVADARIO]

Muito obrigado pela ajuda, terei que procurar a causa da falta de comunicação, você tem alguma ideia do que pode ser? O controlador é novo.

 

[Diesel Dave]

@SILVADARIO , Forum rules are that all posts are to be in English.
See some code #5 diagnostic info below.
.

.

 

[SILVADARIO]

Diesel forgive me, I didn't see that the translator was on.
I will be back on Monday to analyze the excavator, thank you very much for your help, if one day I can help the community I will be grateful.
Thank you very much for the tip and for your time.