KF3 - Check For LFC/HFC Circuit Cycling

- Still in Output State test mode.

- Low Fan Control (LFC) or High Fan Control (HFC) relay disconnected.

- Digital Volt/Ohm Meter (DVOM) on 20 volt scale.

- Connect DVOM positive test lead to the IGN Start/Run circuit and the negative test lead to the LFC or HFC circuit at the LFC/HFC relay vehicle harness connector.

- Depress and release throttle to cycle outputs off.

- While observing DVOM, depress throttle again. For LFC, wait until the Malfunction Indicator Light (MIL) flashes once (10 seconds). For HFC, wait until the MIL flashes twice (15 seconds). Release throttle. The LFC or HFC output is now "on." To cycle "off," depress and release throttle.

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

Yes -- Replace LFC or HFC relay. Remove jumper. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- With Diagnostic Trouble Code (DTC) 563 (HFC) and R-12 A/C refrigerant: Remain in Output State test mode. Leave DVOM connected. Go to KF4. KF4 - Verify Dual Function A/C Pressure Switch Not Closed

All others remove jumper. Go to KF5. KF5 - Check Continuity of LFC/HFC Circuit