TECHNICAL SERVICE BULLETIN - PRODUCT IMPROVEMENT CAMPAIGN PI1803_TSB_R4: KNOCK SENSOR DETECTION SYSTEM - ECU - LOGIC IMPROVEMENT (PI1803) - This bulletin has been revised to include additional information. This bulletin provides information related to a software update to the Engine Control Unit (ECU) to install the Knock Sensor Detection System (KSDS) in order to protect the engine from excessive connecting rod bearing damage.