Mityvac MV4525 COOLING SYSTEM TEST & REFILL KIT - Manual (Page 9)

Temperature Testing (Engine On) continued
Coolant Temperature Sensor
A faulty coolant temperature sensor can cause a multitude of
drivability issues, but can be extremely difficult to diagnose. With
the engine at normal operating temperature, and the thermostat
open, note the temperature reading on the probe. Use a scan tool
to retrieve the coolant temperature from the ECM and compare it
to the probe reading. If they are not within a few degrees, the
sensor should be replaced.
10. When testing is complete, connect the Drain Hose to the Shuttle
Valve using the quick-connect. Make sure the quick-connect
sleeve snaps forward to lock the connection (Fig. 14).
11. Place the opposite end of the Drain Hose into a container
appropriate to capture hot, pressurized coolant. Use the
Hose Clip to secure the Drain Hose in position (Fig. 15).
12. Shift the shuttle valve to the “Open” position, allowing the
hot fluid and pressure to be expelled (Fig. 16).
13. Once all pressure is relieved, cautiously disconnect components,
clean and store them properly.
Caution: Hot fluid being expelled through the test equipment will
cause quick-connects and other metal components to become
hot. Handle such components with care, using a rag if necessary.
14. Refill the radiator or coolant bottle to the proper level, and replace
the cap.
Form 822947 Page Number - 9
Fig. 16
Fig. 14
Fig. 15