Carrier VECTOR 1550 Series Operation & Service Manual

62-61753-21 7-42AlarmNO. Steps ALARM / CAUSE CORRECTIVE ACTION7.7 ELECTRICAL ALARMS71 BAD F2 OR F3 FUSE TRIGGER-ON: F2 &/or F3 has been open for more than 2 seconds: F2, F3 UNIT CONTROL: Engine operation: Alarm Only. If the engine shut off, refer to troubleshootingsteps below to correct.Standby operation: Additional verification required if the "No Power"configuration is set for "Installed and Shut Down" the refrigeration system willshut down with the alarm on and PSCON still energized. RESET CONDITION: Alarm may be manually reset via keypad or by turning the unit off,then back on again.NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, clear thealarm(s). (Refer to Note 1 Page 7-1) Operate the unit through the appropriate modes to see if any active alarmoccurs. Continue with the steps below as necessary.1 Check Unit Operationa. Did engine shut down? Yes, Check F3.No, Check F2.2 Check Fusesa. Locate blown fuse(s). Will have open circuit.b. Verify fuse size. Refer to Section 2.13.Must be correct rating for circuit. (See wiring schemat-ic. Section 10.)c. Inspect fuse & fuse holder. Terminals tight; No signs of overheating, melting ordiscoloration.3 Check Run Relay Circuita. Use Component Test Mode to testactual current draw of the circuit.(Refer to Section 5.1.2.)Check for voltage betweenMPQC-8 and ground.Component FET or board LED (refer to Table 5-1)must be illuminated.View current draw in Data List.Refer to Section 2.12 for normal current values.Voltage should be approximately 12 VDC.b. Check for voltage betweenMPQC-4 and ground.Voltage should be approximately 12 VDC.4 Check Speed Relay Circuita. Use Component Test Mode to testactual current draw of the circuit.(Refer to Section 5.1.2.)Check for voltage betweenMPQC-8 and ground.Component FET or board LED (refer to Table 5-1)must be illuminated.View current draw in Data List.Refer to Section 2.12 for normal current values.Voltage should be approximately 12 VDC.b. Check for voltage betweenMPQC-3 and ground.Voltage should be approximately 12 VDC.