GREE                                                                        GMV5E DC INVERTER VRF UNITS SERVICE MANUAL 
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7. As shown in the figure below, put the black test probe to pad W (RD) and the red test probe to 
pad NW (make sure the moisture proof tape is removed). In normal cases, the multimeter should 
read 0.39±0.3 V. If it is “0” or infinitely great, the IPM module is faulty. 
 
3.2.1.2 Precondition: Units cannot be normally started.  
Step 1: 
Disconnect the power supply of the units and open the electric junction box of the compressor to 
see whether wiring of the compressor is intact.   
Step 2: 
Measure resistance between two wiring terminals (U, V, W). The resistance value range should be 
0.5~2.0 Ω.   
 
Measure the  resistance to  earth  of  each  wiring  terminal.  The  value should  be  10  MΩ.  If  not,  the 
compressor has an internal fault.   
Step 3: 
Check the solenoid valves of the system, include electric expansion valves, oil return valves, and oil 
balance valves. Refer to the preceding section for the test method.   
Step 4: 
Check the IPM module. Refer to the preceding section for the test method.