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Hitachi zx225uslc throttle not working

LACHAU

Senior Member
Joined
Aug 11, 2009
Messages
976
Location
Saigon, Vietnam
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

 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
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..
 

Volvomad

Senior Member
Joined
Jul 13, 2011
Messages
476
Location
Ireland
Is the MC screwed together ? If so it might be worth having a look inside for damp and/or corrosion .
 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
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.
 

LACHAU

Senior Member
Joined
Aug 11, 2009
Messages
976
Location
Saigon, Vietnam
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.
"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



 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
"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.

View attachment 205526


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...
 

LACHAU

Senior Member
Joined
Aug 11, 2009
Messages
976
Location
Saigon, Vietnam
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
 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
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
 

excavator

Senior Member
Joined
Oct 16, 2006
Messages
1,445
Location
Pacific North West
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
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.
 

mg2361

Senior Member
Joined
Jul 5, 2016
Messages
5,057
Location
Pennsylvania
Occupation
Equipment Mechanic
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?
 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
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.
 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
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?
In regards to this valve controller what and where is this??
 

excavator

Senior Member
Joined
Oct 16, 2006
Messages
1,445
Location
Pacific North West
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.
Try doing a throttle re-learn now.
 

mg2361

Senior Member
Joined
Jul 5, 2016
Messages
5,057
Location
Pennsylvania
Occupation
Equipment Mechanic
BUT cant shut off with key

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.

In regards to this valve controller what and where is this??

Behind the seat under the plastic.
 

Martin Canuel

Active Member
Joined
Nov 16, 2019
Messages
31
Location
Prince George, British Columbia
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.
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.
 
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