DRIVE GP-TACHOMETER 9N0016 - Caterpillar

Engine/Generator Setpoint Viewing OP2-0 and Protective Relaying Setpoint Viewing OP2-1 in the Service Mode section.2. Shut down the engine. Remove the positive lead wire from the battery.3. Remove the harness connector from the GSC+. A 4mm hex wrench is required to turn the fastening screw.4. Make sure that all wires at the terminal strips are marked with the respective termination point. During reassembly these wires must be reattached to the correct terminal. Remove all wires from the terminals and posts of the relay module.5. Remove the six nuts that fasten the GSC+ to the instrument door. Remove the GSC+.6. Place the new GSC+ in the instrument door. Install and tighten the six nuts.7. Reconnect the harness connector to the GSC+. Reconnect all the wires to the terminals of the relay module that were removed. Reconnect the positive lead wire to the battery. If necessary, see the Main Chassis Wiring Diagram in the Schematics & Wiring Diagrams section.8. Reprogram the setpoints, the spare inputs/outputs, the hourmeter, the voltmeter/ammeter and the AC offset adjustment. See the related topics in the Service Mode section. Use the values from the original GSC+. If the original values are not available, reprogram using the setpoints of the 136-9048 Control Panel Chart.Relay Module Replacement
Relay Module Replacement (Rear of GSC+)
(1) Relay Module. (2) Screws. (3) Tape. (4) Desiccant package. (5) O-ring seal. (6) Cable connector.Relay module (1) contains the relays, fuses and terminals that are used to operate external devices of the EMCP II+ system. Relay module (1) is a component of the GSC+.Reference: Special Instruction, SEHS9710, Relay Module Replacement. Replacement Procedure1. Remove the positive lead wire from the battery.2. Make sure that all wires at the terminal strips of relay module (1) are marked with the respective termination point. During reassembly these wires must be reattached to the correct terminal. Remove all wires from the terminals and posts of relay module (1).3. Remove ten screws (2) that fasten relay module (1) to the GSC+.4. Be aware that O-ring seal (5) exists. Partially separate relay module (1) from the GSC+. Carefully disconnect cable clamp and cable connector (6) from relay module (1).On the pc board of the original relay module and the replacement relay module, check that the small jumper block (near the ribbon cable) is the same. See the topic AC Voltage Range Selection.5. Replace desiccant package (4) with the new desiccant package and tape that is included with the replacement relay module. Attach the new desiccant package in the same manner as the one removed. Do not remove the new desiccant package from the protective container until immediately before it is installed into the GSC+. Installing the replacement relay module should take approximately 20 minutes. Longer periods of time will cause the desiccant package to become saturated with moisture, particularly if in a humid environment.6. Install new O-ring seal (5) in the groove of relay module (1). Make sure O-ring seal (5) is seated properly. Align and reconnect cable connector (6) to relay module