CYLINDER GP-AIR OVER HYD 8R0860 - Caterpillar

Introduction
When servicing or repairing electric power generation equipment, do the following:a. Make sure the unit is off-line (disconnected from utility power service and/or other generators) and either locked out or tagged DO NOT OPERATE.b. Make sure the generator engine is stopped.c. Make sure all batteries are disconnected.d. Make sure all capacitors are discharged.When power generation equipment is in operation to make tests and/or adjustments, high voltage and current are present. Make sure the testing equipment is designed for and correctly operated for the high voltage and current tests. Failure of improper test equipment presents a high voltage shock hazard to its user.
When the engine-generator, or any source to which the engine-generator is synchronized to, is operating, voltages up to 600V are present in the control panel.Do NOT short these terminals with line voltage to ground with any part of the body or any conductive material. Loss of life or injury could result from electrical shock or injury from molten metal.
Do NOT connect generator to a utility electrical distribution system, unless it is isolated from the system. Personal injury or death is possible by electrical feedback into the distribution system.Open and secure main distribution system switch or, if the connection is permanent, install a double throw transfer switch to prevent electrical feedback. Some generators are specifically approved by a utility to run in parallel with the distribution system and isolation is NOT required. Always check with the utility as to the applicable circumstances.
Service Tools
Fault Identification
GSC+ Display Area
(1) Dedicated shutdown indicators. (2) Spare fault indicators. (3) Fault shutdown indicator. (4) Fault alarm indicator. (5) Upper display. (6) Lower display. (7) Keypad. (8) DIAG indicator.Faults that are detected and diagnosed by the GSC+ are shown to service personnel in the display area of the GSC+. The GSC+ uses dedicated shutdown indicators (1), fault shutdown indicator (3), fault alarm indicator (4), DIAG indicator (8), upper display (5) and lower display (6) to tell service personnel about a fault. Perform the following procedure to identify the fault detected by the GSC+. DIAG indicator (8) functions (either FLASHING or ON CONTINUOUSLY) whenever diagnostic information is available from the GSC+.1. Note which of the indicators are functioning on the left side of the GSC+.2. View the fault code on upper display (5). If fault alarm indicator (4) is FLASHING and no fault code is present on upper display (5), press the alarm codes key to view the fault code.3. Note whether or not DIAG indicator (8) is FLASHING, ON CONTINUOUSLY, or ABSENT.4. On the Fault Identification chart, look at the first column and locate the fault indicator that is functioning.5. Go across to the second column in the chart and find the fault code that is presently shown on upper display (5).6. Go across to the third column in the chart which describes the status of DIAG indicator (8).7. Read the last two columns to find the type of fault and the corresponding topic within this module.Diagnostic Fault Code Troubleshooting
Diagnostic fault codes are associated with