CARRIER-STATOR 1T1908 - Caterpillar

Illustration 1 g01098948
(1) Lift Valve (2) Lift Valve Solenoid (3) Lift Valve Fault Monitoring LED (4) Tilt Valve Fault Monitoring LED (5) Tilt Valve Solenoid (6) Tilt ValveInput Signal Out of Range - The input signal voltage is continuously monitored. The signal range is between 15% and 85% of the supply voltage. An input signal that is outside of this range will switch the system into an active error state.Transducer Feedback Error - If one of the wires to the transducer is broken or shorted, the system will switch to an active error state.Closed Loop Error - The actual position of the valve spool must always correspond to the input signal command. When the distance from the neutral position to the actual position is longer than the commanded input signal, the system will switch to an active error state.
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 keyswitch for the machine to the "OFF" position.
Turn the keyswitch 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 grade control valve turns OFF.Results:
YES - The fault LED on the grade control valve turns OFF. Return the machine to normal operation. Stop.
YES - The fault LED on the grade control valve initially turns OFF, but returns to the ON state. Proceed to test step 3.
NO - The fault LED on the grade control valve does not turn OFF. Proceed to test step 3.Test Step 2. CHECK FAULT LINE
Illustration 3 g01100867
Short pin 3 to pin 4 (ground)Expected Result:Fault indicator LED is no longer ON.Results:
YES - Fault indicator LED is not ON. Proceed to test step 4
NO - Fault indicator LED is still ON. Proceed to test step 3Test Step 3. DETERMINE FAULT STATUS
Illustration 4 g01100867
When this diagnostic code is active, connect a digital multimeter probe to pin 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 Proceed to test step 4
YES - Closed Loop Error Proceed to test step 5Test Step 4. CHECK THE HARNESS FOR AN OPEN.
Move the power/setup switch on the AccuGrade Laser