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257B No Work tool hydraulics

OLDDODGETRUCKS

Well-Known Member
Joined
Nov 17, 2019
Messages
56
Location
CALIFORNIA
Hello,
My 257B Serial SLK06914 will start run and drive fine but the boom arm and bucket functions come and go. Previous owner wired up a bypass switch which sends 12V+ to the orange wire on the right hand joystick solenoid when toggled on to get the work tool to function but bypasses all safteys. I have followed a few trouble shooting procedures i have found online but am not sure if they are the right procedures for my serial number. Can someone send me this procedure for my serial number? I think my interlock ECM is bad but want to be sure by following the proper procedure.

Right now i have no flashing lights (Park of arm rest bar light) just non functioning boom/bucket hydraulics

Also one of the trouble shooting procedures references the "Work tool pilot solenoid". Is this on the work tool control valve under the cab on the right hand side? If so Which one" there are 2 on this large valve.

Thanks
Joe
m37dsl@gmail.com
 

Mark250

Senior Member
Joined
Aug 30, 2015
Messages
1,243
Location
victoria,Australia
Occupation
heavy equipment technician
First off check that the hydraulic lock out switch is not enabled
Be aware that the interlock and aux ECM's do give trouble but you need to do some basic checks before condemning the ECM
Do you have an electrical schematic ? if not do you require one?
upload_2019-11-17_18-37-24.png
second check that the door switch is working correctly if fitted. if the door is not fitted check that a jumper wire has been fitted in place of switch
upload_2019-11-17_18-39-35.png
item 2 is the work tool pilot solenoid
upload_2019-11-17_18-41-36.png

upload_2019-11-17_18-47-46.png
The fact that the machine starts, park brake releases and machine travels means that the arm and seat switch circuits are ok
 

Mark250

Senior Member
Joined
Aug 30, 2015
Messages
1,243
Location
victoria,Australia
Occupation
heavy equipment technician
upload_2019-11-17_18-55-29.png
Here is a fault chart that may help please feel free to ask for any other info that may help you
upload_2019-11-17_18-57-25.png
Mark
 

OLDDODGETRUCKS

Well-Known Member
Joined
Nov 17, 2019
Messages
56
Location
CALIFORNIA
Mark,
I ran a couple checks this morning as you requested:

These tests are ran with the original wiring in place (No 12v+ hot wire to the work tool pilot solenoid)

-Machine starts, no fault indicators, parking brake releases and it will drive but no work tool hydraulics (Arms/Bucket)

-Hydraulic lock out switch
This switch is not enabled, i double checked by trying it in any position, side note i do not get an indicator on the display no matter what position this switch is in.

-Door switch
This unit originally had a cab/door which was removed by the previous owner. In doing this the "Jumper wire" required to bypass the door switch is in place in the form of a scotch lock connector (see attached picture)

Can you send me the troubleshooting procedure for my Serial number so i can pinpoint where in the interlock system i have a fault?
 

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OLDDODGETRUCKS

Well-Known Member
Joined
Nov 17, 2019
Messages
56
Location
CALIFORNIA
I followed the below "Work tool does not Function" troubleshooting procedure and here is where i am at:

Step 1 result: OK (No fault lights) on to step 2

Step 2 result: the resistance from contact 24 to contact 68 (wire P988-OR to wire 975-WH) of the wire harness connector is 9.8 Ohms.... (Supposed to be 6?) on to step 3?

Step 3 result: OK (10 ohms measured at Work tool pilot solenoid) on to step 4

Step 4 result: Not OK NO RESISTANCE measured at the work tool detent coil

Does this mean the work tool detent coil is bad and causing all these issues?

I also checked continuity from the ecm plug to the work tool pilot solenoid and detent solenoids to check for shorts/continuity and everything looks good.

Work Tool Does Not Function





System Operation Description:


The Interlock ECM will NOT engage the work tool pilot solenoid if problems exist with the parking brake switch or the work tool pilot solenoid.


Note: Use a jumper wire on machines that do NOT use a lockout switch for the work tool. The jumper wire is 165-0312 Wire Assembly. This jumper wire is fastened to the harness in place of the switch. The jumper must be connected in order to allow both the primary work tool and the auxiliary work tool to operate.


Test Step 1. CHECK THE FAULT INDICATORS


  1. Occupy the seat.
  1. Lower the armrest.
  1. Turn the key start switch to the ON position.
  1. Press and release the parking brake switch.

Expected Result:


The armrest indicator and the parking brake indicator should be off.


Results:


  • OK - The armrest indicator and the parking brake indicator are off. Proceed to Test Step 2.




  • NOT OK - The parking brake indicator remains on.
    Repair: See Troubleshooting, "Switch (Parking Brake)".


    Stop.




Test Step 2. CHECK THE CIRCUIT OF THE WORK TOOL PILOT SOLENOID


  1. Turn the key start switch to the OFF position.
  1. Raise the cab. See Operation and Maintenance Manual, "Cab Tilting".
  1. Locate the interlock ECM. The interlock ECM is located on the left side of the machine beneath the access cover on the floor of the machine.
  1. Remove the wire harness from the ECM.
  1. Measure the resistance from contact 24 to contact 68 (wire P988-OR to wire 975-WH) of the wire harness connector.

Expected Result:


The resistance should be approximately 6 Ohms.


Results:


  • OK - The resistance is approximately 6 Ohms.
    Repair: The ECM is very unlikely to have failed. Reconnect all connections and visually inspect the wire harness. Verify that the diagnostic code still exists. If the diagnostic code still exists perform the Test Steps again.Replace the ECM, if the cause of the diagnostic code was not found after the second attempt. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace".


    Stop.






  • NOT OK - The resistance is not approximately 6 Ohms. Proceed to Test Step 3.

Test Step 3. CHECK THE RESISTANCE OF THE WORK TOOL PILOT SOLENOID


  1. Locate the work tool pilot solenoid.
  1. Disconnect the wire harness from the work tool pilot solenoid.
  1. Measure the resistance of the two wires on the work tool pilot solenoid.

Expected Result:


The resistance should be approximately 10.5 Ohms.


Results:


  • OK - The resistance is approximately 10.5 Ohms. Proceed to Test Step 4.




  • NOT OK - The resistance is not approximately 10.5 Ohms.
    Repair: The solenoid has failed. Replace the coil.


    Stop.




Test Step 4. CHECK THE RESISTANCE OF THE WORK TOOL DETENT COIL


  1. Locate the work tool detent coil. The detent coil is located beneath the right hand joystick. Remove the access panel in order to get to the connector.
  1. Disconnect the wire harness from the work tool detent coil .
  1. Measure the resistance of the two wires on the work tool detent coil.

Expected Result:


The resistance should be approximately 10.5 Ohms.


Results:


  • OK - The resistance is approximately 10.5 Ohms.
    Repair: The wire harness has failed. Repair the wire harness and/or the connector or replace the wire harness and/or the connector.


    Stop.






  • NOT OK - The resistance is not approximately 10.5 Ohms.
    Repair: The work tool detent coil has failed. Replace the the work tool detent coil.


    Stop.
 

OLDDODGETRUCKS

Well-Known Member
Joined
Nov 17, 2019
Messages
56
Location
CALIFORNIA
Update went back to square one found the jumper wire (Scotch lock connector previous owner had installed pictured above) for the door switch had a bad connection between the white and black wires, hoping this is my fix!!
 
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