HINGE AS 8V0388 - Caterpillar

Switch Circuit Diagnostics
A problem exists with a switch and further troubleshooting is necessary in order to isolate the problem.The possible causes of these failures are as follows:
The signal circuit in the machine harness is open.
The switch has failed.
The ECM has failed.Check For An Open In the Harness
Locate the switch that corresponds to the indicator that is located on the display of the operator advisor. (If necessary, use the electrical system schematic to assist in locating the switch.)
Disconnect the signal wire from the switch.
Place a jumper wire from the signal wire to the ground wire.Expected ResultThe alert indicator is no longer active on the display module.OK - The alert indicator is no longer active on the main display module.Repair - The switch has failed. Check or replace the switch.STOP.Not OK - The alert indicator remains on the main display module. The machine harness is open or the ECM has failed. Proceed to "Check The Voltage Of The Module".Check The Voltage Of The Module
Remove the jumper that was used in the previous test step.
The signal wire remains disconnected.
Measure the pull-up voltage from the signal wire to the ground wire with a digital multimeter.
Determine the correct voltage spec for the circuit being tested. Expected ResultThe voltage is correct for the circuit tested.OK - The switch circuit voltage is within spec.Repair - The voltage is correct. ECM failure is unlikely. Exit this procedure and perform this procedure again. If the problem persists, the ECM may have failed. Prior to replacing an ECM, always contact your dealership for