SENSOR GP-PRESSURE 1439176 - Caterpillar

Engines: 3508B (S/N: 1TW1; 2BM1; 2HW1; 3DM1; 3DW1; 3LS1; 3PS1; 3TS1; 4GM1; 5PS1; 5XM1; 6PN1; 7SM1) 3512B (S/N: 1PW1; 2EZ1; 2GW1; 2RD1; 2TD1; 3MS1; 3RS1; 3WS1; 3ZW1; 4AW1; 4TN1; 5AW1; 6PM1; 6WN1; 7HM1; 8EM1; 8RM1) 3516B (S/N: 1NW1; 2JW1; 2FW1; 3CW1; 3NS1; 3SS1; 3XS1; 4BW1; 6HN1; 6HZ1; 7KM1; 7RN1; 8CN1; 8KN1; 9AN1)Introduction
This Special Instruction will modify the emergency stop circuit on the Electronic Instrument Panel. The existing circuit will allow the engine to restart after the emergency stop button is reset. The modification will change the circuit so that the Engine Control Switch must be reset after an emergency stop shutdown in order to restart the engine.This modification is recommended for the 3500B engines that are used in the following applications: marine propulsion, marine auxiliary with the Electronic Instrument Panel (EIP), land and offshore petroleum engines with the EIP and land EPG with the EIP. This modification is not for the EMCP II/II+ generator sets.This Special Instruction contains the procedures for modifying engines with premium wiring and for modifying engines with standard wiring. Verify which wiring package (standard or premium) that your engine has, and follow the corresponding procedures.Description and FunctionThis modification changes the emergency stop circuit. The change will require the Engine Control Switch (ECS) to be reset after an emergency stop shutdown in order to start the engine. The current emergency stop circuit will initiate cranking after the emergency stop button is reset without resetting the ECS. Once the modification is installed, pushing the emergency stop button will remove power from the Primary Engine Control Module (PECM) relay and the Secondary Engine Control Module (SECM) relay. The PECM relay then removes power from the Primary ECM. The SECM relay removes power from the Secondary ECM. The emergency stop lockout relay and the emergency stop relay energize in order to complete the circuit for the PECM relay and the SECM relay. These relays stay energized until the ECS is placed in the OFF/RESET position. Resetting the emergency stop switch will not allow the engine to start until the ECS has been placed in the OFF/RESET position, and then to START or AUTO.Glossary of TermsADEM Box - The ADEM box contains the PECM and the SECM. The premium wiring and instrumentation package contains the ADEM box.Engine Control Module (ECM) - The ECM is referred to as the ADEM II on 3500B engines.Engine Control Switch (ECS) - The ECS is located on the EIP or on the ADEM box. The ECS is the master control for the engine.Emergency Stop - An emergency stop is a method to shutdown the engine in an emergency. An emergency stop shutdown is not used for routine engine shutdowns.Electronic Instrument Panel (EIP) - The EIP is used with standard wiring on the following applications: marine, marine auxiliary, petroleum and land based package generator sets. Engine Monitoring System (EMS, EMS-II and EMS-III) - This module is used to indicate up to ten alarms and shutdowns. The module will also indicate a numeric value for various