DAV-SZ1000W, HBD-SZ1000W (serv.man2) - Sony Audio Service Manual (repair manual). Page 10

1. When AC power supplies voltage to the SUB POWER TRANSFORMAER(T903),  

FAN14V output signal is output. This signal is input  to the FAN 
DRIVE(Q3000,Q3002) and then the DC FAN(FAN3001) starts spinning at low 
speed.

2. When the SUB WOOFER outputs in high volume, the signal is input to the FAN 

DRIVE(Q3000,Q3002) and the DC FAN(FAN3001) starts spinning at high 
speed.(Refer to P.18)

(Note) Spinning of the fan

If th DC FAN d

t

i

th t

t

i

id th

it

ill i

Thi

•

If the DC FAN dose not spin, the temperature inside the unit will increase. This 
may cause the unit to stop operating along with the display “Protector” on the 
FLUORESCENT INDICATOR TUBE.

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