22003082 Volvo.Penta Protecting screen

The following background information is related to this procedure:NRS (EGR) ValveThe NRS valve is used to control the amount of exhaust gas which is recirculated into the intake manifold.The amount of exhaust gas that is required is calculated by the software that is contained in the ECM. The NRS valve is controlled by a PWM signal from the ECM.Intake Throttle ValveThe intake throttle valve is used to increase the exhaust gas temperature to aid the regeneration process."Air System Motor Valve Verification Test"The "Air System Motor Valve Verification Test" will identify whether the NRS valve and the intake throttle valve are working correctly. This test must be performed when the engine speed is zero and the battery voltage is within an acceptable range. For a 12V system, the test must only be performed when the battery voltage is between 9V and 16V. For a 24V system, the test must only be performed when the battery voltage is between 18V and 32V. If the battery voltage is out of the required range, the test will be aborted.The "Air System Motor Valve Verification Test" will actively check position sensor diagnostics, motor short diagnostics, and motor open circuit diagnostics. The test will abort if any of these diagnostic codes become active.If the engine speed is zero while the test is being performed, the test will be aborted. If no electrical diagnostic codes are active, the test will calibrate the NRS valve minimum position and the intake throttle valve minimum and maximum position. The test then moves the valves to various positions and checks the position sensor within each valve to confirm that the valve has responded correctly. Each valve will be tested in turn, starting with the NRS valve. If a test threshold is exceeded or any related diagnostic codes become active, the test will abort and generate a service tool error identifier."Engine Throttle Valve Replacement Test"The Engine Intake Throttle Valve minimum and maximum positions are calibrated automatically at each key off and stored in the ECU non-volatile memory (NVM) to ensure accurate range over the life of the product. Engine Intake Throttle Valve usage information is also stored in NVM. After replacement of the Engine Intake Throttle valve, the "Engine Throttle Valve Replacement Reset" should be run to reset the minimum and maximum position calibrations to their nominal values and reset the usage information. The "Air System Motor Valve Verification Test" should then be run to recalibrate the specific minimum and maximum positions for the new Engine Intake Throttle Valve."EGR Valve Replacement Test"The EGR Valve minimum position is calibrated automatically at each key off and stored in the ECU non-volatile memory (NVM) to ensure accurate range over the life of the product. EGR Valve usage information is also stored in the NVM. After replacement of the EGR Valve, the EGR Valve Replacement Reset should be run to reset the minimum position calibration to the nominal value and reset the usage information. The Air System Motor Valve Verification Test should then be run to recalibrate the specific minimum position for the new EGR Valve.
Illustration 1 g06366265
Schematic diagram for the motorized valves
Table 2
Troubleshooting Test Steps Values Results
1. Inspect Electrical Connectors and Wiring
A. Thoroughly inspect connectors for the motorized valves. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
B. Thoroughly inspect the engine interface connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Damaged wire or connector
Result: A damaged wire or damaged connector was found.
Repair: Repair the damaged wire or the damaged connector.
Use the electronic service tool to clear all