IDLER GP-FRONT 3927374 - Caterpillar

The secondary steering system provides temporary steering control when the primary steering system does not operate properly. The implement ECM sends a request to the power train control ECM if the secondary steering system needs to be activated.Electronic Control
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(5) Secondary steering indicator (6) Action lamp indicatorAfter the engine has been started, the power train control ECM checks the operation of the secondary steering pump if equipped. The power train control ECM will energize the secondary steering relay to activate the secondary steering motor. The implement ECM monitors the secondary steering pump pressure sensor for an increase in steering system pressure. Secondary steering warning indicator (5) activates for 3 seconds. This condition occurs only if the machine is equipped with the optional secondary steering attachment. After 3 seconds, the alert indicator for secondary steering (5) will shut off. Investigate the cause of the fault if the alert indicator for secondary steering does not activate. Do not operate the machine until the fault has been corrected.Secondary Steering Indicator (5) will be amber in color when the secondary steering system is active or the secondary steering system is being tested. The alert indicator will be red in color when a problem with the secondary steering system exists.Warning Category 3 occurs when there is a loss of primary steering oil pressure in the steering system. This condition occurs if the machine is equipped with the optional secondary steering attachment. Warning Category 3 will activate secondary steering indicator (5) and also causes master action lamp (6) to flash. The action alarm also sounds and an active fault message appears on the graphical display.
The alarm system indicates that the primary steering system has failed.Use the secondary steering system to steer the machine to the nearest convenient location. When the machine comes to a complete stop, turn the start switch key to the OFF position.Continuing to operate the machine may result in damage to the system.
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Secondary steering control (2) Secondary steering motor relay (If equipped) (4) Steering pressure sensors (7) Power Train ECM (8) Operator present (9) Left-hand steering control (10) Left armrest switch (11) Feedback motor control (12) Steering control spool position sensor (13) Left secondary steering solenoid (14) Right secondary steering solenoid (15) Transmission output speed (from power train ECM) (16) Steering cylinder position sensors (17) Implement ECMThe operation of the secondary steering system controls the steering system of the machine in same manner as the primary steering system. The Power Train ECM uses input components, output components, and information from the Data Links to control the steering control valve.Inputs for the Power Train ECM include:
Transmission Output Speed (TOS)
Operator present switch
Left-hand steering control
Steering control spool position sensor
Steering cylinder position sensors
Steering system pressureOutputs for the Power Train ECM include:
Right secondary steering solenoid
Left secondary steering solenoid The Implement ECM will send the request signal to activate the secondary steering system when any of the following machine system conditions are detected:
An active CID 2199 "Secondary Steering Request from Implement ECM" diagnostic code is