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Hitachi zx225uslc throttle not working

Discussion in 'Excavators' started by Martin Canuel, Nov 18, 2019.

  1. LACHAU

    LACHAU Well-Known Member

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    ZX225USLC has 2 controller: MC = Main Controller and the other is ICX controller = Information Controller.
    Don't care about ICX controller. It's just stored the information that send as a report for management!!!

    MC CONNECTOR.png

    ICX 2.png
    ICX 1.png

     
  2. LACHAU

    LACHAU Well-Known Member

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    Do you have the Dr.ZX manual already my friends??
    ScreenShot_20191119194645.png

    ScreenShot_20191119194609.png
     
  3. Martin Canuel

    Martin Canuel Active Member

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    Yes apologies it is a 6 pin plug for the dr.zx the icx and mcx are both 6 pins
     
  4. Martin Canuel

    Martin Canuel Active Member

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  5. Martin Canuel

    Martin Canuel Active Member

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    Fired up this morning throttle working fine. Hate this intermittent issue

    while throttle is actually working for the moment i Still did readings on the ec sensor circuit. read 2.19v between #2and#3 at idle and read 1.91v at full throttle
    which doesnt make sense to me as slow idle should be 2.5-2.7 and full 3.3 to 3.7

    The diagram for testing the ec motor circuit is confusing me the am i checking /probing these circuits to test for a volage or resistance?? and which terminals of the 4 on the ec motor circuit do i test as the diagram for the st7125 just shows them all on one..

    Dr.zx still wont communicate

    i am unable to read any vales as well on the screen while pressing the set button...

    The throttle dial according to the flow diagram would only be responsible for engine speed it says its not related to the key off problem iam having..
     
  6. mg2361

    mg2361 Senior Member

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    Voltage.
     
  7. Volvomad

    Volvomad Senior Member

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    Is the MC screwed together ? If so it might be worth having a look inside for damp and/or corrosion .
     
  8. Martin Canuel

    Martin Canuel Active Member

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    Throttle was working today with the dial however still cant shut off with key, cannot read any values on the screen by pressing the set button, and drzw wont communicate.

    good idea about taking the ecm apart, thats probably all thats left.
    Think i may just bite the bullet and get a ecm and the throttle dial panel.
     
  9. LACHAU

    LACHAU Well-Known Member

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    "Throttle was working today with the dial" is good information.
    "however still cant shut off with key" don't worry about this. You can try to adjust the linkage between EC motor and Control cable.

    000.png



     
  10. Martin Canuel

    Martin Canuel Active Member

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    Iam assuming your thinking that the servo motor is just not pushing or pulling the cable all of the way to shut the motor off then??

    Would not being able to see any of the settings on the screen/cluster by pressing display be related?
    As well as the no communication issue with the dr.zx...
     
  11. LACHAU

    LACHAU Well-Known Member

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    Yes, I've.
    OK. You should just adjust the cable, no need to perform "ENGINE LEARNING".
     
  12. LACHAU

    LACHAU Well-Known Member

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    Regarding to Dr.ZX didn't recognized your machine. Please take a photo of Palm PDA let us refer to.

    It look like follow image??

    ScreenShot_20191120145540.png
     
  13. Martin Canuel

    Martin Canuel Active Member

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    Alright SUCCESS IN CONNECTING THE DR.ZX
    Codes read 6,13,15,16,18
    Faulty ec sensor
    faulty pump 2 pump control pressure sensor
    Faulty boom raise pilot p. sensor
    Faulty roll-in pilot pressure sensor
    Faulty travel pilot pressure sensor

    Now going forward are all of these codes related to one harness possible?
    Also do these codes go away when fixed or do you clear them with the dr.zx?

    I was able to read the ec sensor voltage with the dr.zx
    idle-2.83v
    full throttle - 3.08v

    Dial volatge idle - 0.56
    dial voltage full throttle - 4.33
     
  14. excavator

    excavator Senior Member

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    Not sure about the bottom 3 sensors but I have had it on a -5 machine where a faulty pump sensor will shut down the main controller, not allowing computer access or throttle control. When the machine starts giving you problems again, turn off the key, unplug pump 2 sensor and see what happens. I've also had an intermittent problem like this and it was the harness plug going into the sensor. Deere does sell individual harness plugs for this.
     
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  15. mg2361

    mg2361 Senior Member

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    As I stated in post #2, any short in the 5 V reference circuit of any sensor will shut down the controller as well as have an effect on the other sensors. So expanding on what excavator said keep unplugging sensors one at a time (with a key cycle) to see if the problem goes away. Keep in mind that this checks sensors and not the wiring.
    For what it is worth I found the voltage specs for the 4 pin diagnostic connector and their respective voltages so you have it for future reference.
    • Pin 1 - 0 volts (black/blue wire)
    • Pin 2 - 0 volts (this is actually frame ground)(black wire)
    • Pin 3 - .097 - .098 volts (black/green wire)
    • Pin 4 - 5.25 - 5.30 volts (red/blue wire)
    Also, (you may have mentioned and I missed it) when your issue is happening is the light on the pump and valve controller blinking, lit solid, or does it go out?
     
  16. Martin Canuel

    Martin Canuel Active Member

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    Did some unplugging today
    AT this time dr.zx connected and throttle working with dial, BUT cant shut off with key still
    i had the drzx monitoring all 4 sensors
    unplugged the 4 sensors that had codes one at a time and watched the values disappear however no time did i regain the ability to shut off with key as i tried every time when i unplugged each sensor
    after all was done i re-scanned codes and no codes were present "problem not found in diagnostic system" was the message i got when reading diagnostic codes.
    engine dial and ec sensor vales were reading fine on the dr zx as well

    still cant turn off with key, i have to use manual shut off.
     
  17. Martin Canuel

    Martin Canuel Active Member

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    In regards to this valve controller what and where is this??
     
  18. excavator

    excavator Senior Member

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    Try doing a throttle re-learn now.
     
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  19. mg2361

    mg2361 Senior Member

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    As far as not being able to shutting it off with the key, I suspect you have a bad V2 alternator relay shut down diode. The V2 diode is located behind the seat close to the fuse panel (under the plastic covers) and can be identified by the red/white and red/black wires going to it. Try swapping it with another diode (should be more than one there) to see if that fixes your shut down issue.

    Behind the seat under the plastic.
     
  20. Martin Canuel

    Martin Canuel Active Member

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    I have swapped all the diodes back and forth with no results, trying each time to turn off with key...still cant turn off with key.