HOSE AS 3922584 - Caterpillar

Changes That Are Common To All Commercial Engines
1. The pressure sensor signals are now filtered electronically. Electronic filtering helps reduce erratic signals and provides the following results:* Helps eliminate false "air inlet restriction" events* Helps eliminate false "high crankcase pressure" events* Stabilizes fuel pressure readings* Stabilizes oil pressure readings2. A change was made to eliminate false logging of 94-02 and 289-02 (fuel pressure sensor installed incorrectly) codes. Some engines, that are equipped with duplex filters, would log these codes if the engine was shut down while the Electronic Control Module (ECM) was still powered. The new software requires a minimum engine speed of 200 rpm before the 94-02 and 289-02 codes can be registered. The following circumstances most likely indicate that the fuel pressure sensors are installed incorrectly (the "filtered" sensor and the "unfiltered" sensor might be reversed):* The new software does not eliminate the 94-02 and 289-02 codes.* The 94-02 or 289-02 codes are active, but the engine does not have the duplex filters option.* The 94-02 and 289-02 codes become active INITIALLY when the engine is running.* The unfiltered fuel pressure is lower than the filtered fuel pressure, when viewed on the ET Status Screen. For better resolution, use metric units (kPa) rather than English units (psi) when checking fuel pressure on the ET Status Screen.Changes To Marine Engines Only
1. A change has been made in order to help eliminate intermittent "!STOP" light flashing on the EMS II module. Intermittent "!STOP" light flashing, which would occur without logging an event code, affects only marine propulsion engines. Marine propulsion engines are equipped with a primary ECM and a backup ECM. This arrangement requires a unique communication strategy between the two ECMs. The "!STOP" light would flash when the backup ECM status changed from "ready" to "not ready". The software has been upgraded to eliminate the false "not ready" condition in the backup ECM.2. Incorrect 248-02 (data erratic, intermittent, or incorrect) diagnostic codes have been resolved. This problem had occurred on engines that are equipped with the Pilothouse Control Panel option. The problem occurred because of an overload of data link traffic. The new software strategy reduces data link traffic and eliminates the 248-02 issue by staggering EMSII and Pilothouse EMS messages.3. The new software allows the Engine Vision to properly display negative crankcase pressure readings. This change will help eliminate false "Error" readings.Changes To Marine Auxiliary And Generator Set Engines Only
1. The low idle speed parameter can now be programmed above 1000 rpm. This improvement is especially useful for applications that use the former 131-5459 Governor Control (Load Sharing Module). The 131-5459 Governor Control receives power from the generator potential transformers. Some generators may not produce sufficient voltage at 1000 rpm to "power up" the load sharing module. For an engine that is rated at 1800 rpm, the low idle speed should generally be 1200 rpm.2. There is now a dedicated low idle switch input. This change affects the operation of the low idle switch that is