PISTON 0020659 - Caterpillar

Illustration 2 g01094319
Test Step 1. CYCLE POWER TO THE SYSTEM
Move the "power/setup" for the AccuGrade Laser system to the "OFF" position.
Turn the key start switch for the machine to the "OFF" position.
Turn the key start switch for the machine to the "ON" position.
Move the "power/setup" for the AccuGrade system to the "ON" position.Expected Result:The fault LED on the right (tilt) grade control valve turns OFF.Results:
YES - The fault LED on the right (tilt) grade control valve turns OFF. Return the machine to normal operation.STOP
YES - The fault LED on the right (tilt) grade control valve initially turns OFF, but returns to the ON state. Proceed to Test Step 3.
NO - The fault LED on the right (tilt) grade control valve does not turn OFF. Proceed to Test Step 3.Test Step 2. CHECK FAULT LINE
Illustration 3 g01100867
Illustration 4 g01109358
(1) Pin 1 (2) Pin 2 (3) Pin 3 (4) Pin 4 (GND) (5) Fault Indicator LED (6) Connector Cover
Remove the connector cover in order to expose the contacts on the coil. Refer to Illustration 4.
Short pin 3 (3) to pin 4 (ground) (4) Expected Result:The fault indicator LED is no longer ON.Results:
YES - The fault indicator LED is not ON. Proceed to Test Step 3
NO - The fault indicator LED is still ON. Proceed to Test Step 3Test Step 3. DETERMINE FAULT STATUS
Illustration 5 g01100867
When this diagnostic code is active, connect a digital multimeter probe to pin 3 (3) in ordr to monitor the output. Refer to the LED status in Table 1 in order to detemine the fault status.
Table 1
Solenoid Module Fault Status    
               
Error Mode     Error Output Status     Fault Output Voltage (1)     LED (2)    
               
No Fault     LOW     <2 VDC     GREEN    
Input Signal Faults     HIGH
    System Voltage
    Flashing RED
   
Transducer Fault     HIGH
    System Voltage     Constant RED    
Closed Loop Fault     HIGH     System Voltage     Constant RED    
( 1 ) Measured between Pin 3 and Ground (Pin 4)
( 2 ) LED will only be ON when a signal is applied to the valve.Expected Result:Expected result will be one of the following:Input signal out of range.Transducer Feedback ErrorClosed Loop ErrorResults:
YES - Input signal out of range. Proceed to Test Step 5
YES - Transducer Feedback Error or Closed Loop Error Proceed to Test Step 4Test Step 4. CHECK THE HARNESS FOR AN OPEN.
Move the "power/setup" switch on the AccuGrade Laser display to the OFF position.
Turn the key start switch and the disconnect switch for the machine to the OFF position.
Disconnect one end of the harness from the interface valve module at connector "GV-C1".
Disconnect the other end of the harness from the right (tilt) valve module at connector "GV-C3".
Measure the resistance between pin "F" on the interface valve module end of the harness and pin "3" on the right (tilt) valve end of the harness. Note the resistance measurement.Expected Result:The