Carrier 38MGR Series - DIAGNOSIS AND SOLUTION: IPM;BOARD TESTS; IPM Board and Voltage Testing

38 Specifications subject to change without notice. 38MGR-04SM
DIAGNOSIS AND SOLUTION (CONT)
Fig. 43 —Test the DC voltage
Use a multimeter to test the DC voltage between the L2 port and S port of the outdoor unit. The red pin of the multimeter connects with the L2
port while the black pin is for the S port. When AC is running normally, the voltage moves alternately between positive and negative values.
Fig. 44 — IPM (For dual/tri-zone)
Standby