GEAR 8E5906 - Caterpillar

measurement should measure battery voltage for approximately 0.5 to 2 seconds after the "Drop" switch is pressed.Expected Result:The voltage measurement is battery voltage at all pins of the wire circuit (T979-YL).Results:
YES - The voltage measurement is battery voltage at all pins of the circuit (wire T979-YL).Repair: The circuit of wire (T979-YL) has failed. Repair the machine harness that includes the failed circuit or replace the machine harness that includes the failed circuit.STOP
NO - The voltage does not measure battery voltage at one or more pins of the circuit (wire T979-YL). Repair: The "Drop" switch at the LH joystick and/or the magnet lockout relay at the fuse and relay base inside the cab may have failed. Check these components and if necessary replace the "Drop" switch and/or the magnet lockout relay. Verify that the problem has been solved.
On machines with serial number prefix (D3XD9X) (D-Series Update), the magnet lockout relay has been removed. This lockout functionality is covered from the machine controller. Refer to Electrical Schematic UENR1270. Proceed to Test Step 5.Test Step 5. CHECK THE VOLTAGE AT THE MAGNET CONTROLLER FOR THE DROP RELAY INPUTS
Set the digital multimeter to the scale for VDC.
Connect the positive lead of the multimeter to J2-3 (wire G889-GY) . Connect the negative lead of the multimeter to J1-70 (wire 201-BK) . Refer to Electrical Schematic KENR9563 or UENR1270.
Press the "Lift" switch in order to initiate a lift cycle.
Measure the voltage as the "Drop" switch is pressed.Note: The voltage must be measured as the "Drop" switch is pressed. The voltage measurement should measure battery voltage for approximately 0.5 to 2 seconds after the "Drop" switch is pressed.Expected Result:The