Pioneer 1014TX-K - THX Select A/V Receiver Service Manual page 129

5
• When MCACC is turned to ON
(SurroundBack is not out with the setting.)
• Suppose CR to be poor contact and that is not damaged.
• This shows failure analysis of DSP Assy.
Step 0: Preliminary check
• Tighten the COAX Jack screws.
(GND of the DSP module floats from the chassis. And this unit
may not work normally, because the electric potential becomes
unstable.)
Step 1: Mute pin
IC801
MUTE (pin 54)
Is
output signal
0V ?
Yes
End
Step 2: B to B connector
CN901
Is
connector
inserted
tight ?
Yes
CN701
Is
connector
inserted
tight ?
Yes
CN951
Is
connector
inserted
tight ?
Yes
End
5
6
No
Replace IC801
No
Turn the power off and
Insert it tight
No
Turn the power off and
Insert it tight
No
Turn the power off and
Insert it tight
6
7
Step 3: Regulator IC
IC901-pin 1 (to chassis)
Is
there the input
of 5V ?
Yes
IC901-pin 3 (to chassis)
Is 3.3V
outputting it ?
Yes
IC902-pin 2 (to chassis)
Is 1.25V
outputting it ?
Yes
End
Step 4: 3 → 5V conversion
IC952
Pin 3
Does
it convert
3V into 5V for
17 pin input?
Yes
Pin 5
Does
it convert
3V into 5V for
15 pin input?
Yes
Pin 7
Does
it convert
3V into 5V for
13 pin input?
Yes
A
VSX-52TX
7
8
No
Check CN901 and
REGULATOR Assy
No
Replace IC901
No
Replace IC902
No
Replace IC952
No
Replace IC952
No
Replace IC952
8
A
B
C
D
E
F
129