Engine Temperature Control Actuator - N493-, Checking

General Description

The rotary coolant valve (RCV) module combines several elements (thermostat, valves, coolant pump, etc.) into one component. Two mechanically connected RCVs are part of the module. The position of RCV 1 controls the coolant flow through the engine oil cooler, the cylinder head, and the main radiator. The RCV 2 controls the coolant flow through the cylinder block. The engine temperature can be adjusted to an optimum value regarding engine speed and load. In addition, the engine heat-up to optimum operating temperature is accelerated by the fact that the coolant circulation can be minimized. A position sensor detects the position of RCV 1. The monitor detects a stuck RCV. An emergency thermostat opens the main cooling circuit if the engine temperature is too high.

Special tools and workshop equipment required 

• Multimeter.
• Wiring Diagram.
• Scan Tool.

Test requirements

• Fuses OK.
• Battery voltage OK.
• Switch OFF all electrical and electronic accessories.
• Vehicles with automatic transmission, ensure the selector lever position is in "P".
• Vehicles with manual transmission, ensure the shifter lever position is in "N" with the parking brake applied.
• Observe all safety precautions: SAFETY PRECAUTIONS .
• View clean working conditions: CLEAN WORKING CONDITIONS .

Test Procedure