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Home >> Mercury >> 1994 >> Tracer L4-116 1.9L SOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Pinpoint Tests >> KF - Low Fan Control/High Fan Control >> KF4 - Verify Dual Function A/C Pressure Switch Not Closed
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KF4 - Verify Dual Function A/C Pressure Switch Not Closed



- Still in Output State test mode.

- High Fan Control (HFC) relay disconnected.

- Disconnect dual function A/C Pressure Switch (ACPSW) (also known as Refrigerant Containment/Fan Function Switch).

- Digital Volt/Ohm Meter (DVOM) connected to IGN Start/Run circuit and HFC circuit at the HFC relay vehicle harness connector.

- Again, cycle throttle to turn HFC output "On" (refer to KF3).

- Does voltage now cycle high and low (about 1.0 volt change)?

Yes -- Key "OFF". Remove jumper. Reconnect HFC relay. Go to Heating and Air Conditioning/Testing and Inspection to check closed ACPSW medium pressure contacts.

No -- Remove jumper. Reconnect ACPSW. Go to KF5. KF5 - Check Continuity of LFC/HFC Circuit
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