Carrier NDK33BN0KB, Operation & Service Manual

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62-61753-21 7-55
Alarm
NO.
Steps ALARM / CAUSE CORRECTIVE ACTION
109 CHECK EVCON COIL

TRIGGER-ON: Evaporator fan motor contactor (EVCON) current is excessive

UNIT CONTROL: Engine and standby operation: alarm only.

RESET CONDITION: Auto Reset or 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, the active
alarm should clear itself (refer to reset condition above). Operate the unit through the appropriate modes to see if
any active alarm occurs. Continue with the steps below as necessary.
1 Check EVCON
a. Inspect evaporator fan contactor
coil and terminals
No damage to coil
No damaged or corroded pins
b. Check contactor coil resistance Refer to Section 2.12. Cannot be opened (infinite
ohms); Shorted (Zero Ohms) or shorted to ground
2 Check EVCON Current Draw
a. Use Component Test Mode to test
actual current draw of the circuit.
(Refer to Section 5.1.2.)
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.
3 Check EVCON
a. Inspect harness & control box
connector pins & terminals. (See
wiring schematic Section 10.)
No physical damage to harness.
No damaged or corroded pins.