Voltronic Axpert VM IV - Check the Buck Circuit on Main Board

16
test result is not right.
3.3 Check the buck circuit on MAIN board
Power devices
BUCK MOSFET and Diode: Q31/D13
For VMIV-5600 the IGBTs Q31 is (IGBT ST/STGW60H65DFB 60A 650V N BULK TO-247)
For VMIV-3600 the IGBTs Q31 is (STGW45HF60WDA 45A 600V NPN BULK TO-247)
The D13 is (RHRP1560 15A 600V UFST RAD BULK)
Parts
Attribute
Reference values
Failure status
Q31
Resistor
GE: 22.8k
GC: 49.5k
CE: OL
Short or explosion
Diode
CE: OL
EC: 0.393V
D13
Resistor
+ to -: 195k
- to +: OL/OL
Diode
+ to -: 0.39V
- to +: OL