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One Point Repair Instruction
No. : AV-HT-2010-06
Registration Date March 15th, 2010 Writer
ECO No. Approver
Effective Date March 15th, 2010 Serial No.
Subject No audio in any function, when you press on the Stand-by/On button.
Applicable Model HT564/904/964
No. Location No. Part No. Desc / Spec Remark
IC701 ~
1 Check Via Hole
IC704
Symptom Details (How to Duplicate Problem)
After pressing the "Stand-by/On" button, you do not hear audio through the speakers in any
function.
How to troubleshoot (Countermeasure)
1. Measure the voltage CN902 (1,2 and 3 Pin) by multimeter. If the voltage
is not about 36V, SMPS Board or other part have defect.
2. Measure the voltage between each speaker output and GND (chassis). If the value is not
about 18V (17.7 ~18V DC = 36V/2(half)), the amplifier IC is NG.
3. If one or more of the outputs FL+, FL-, RL+, RL- have abnormal Voltages (Only 10V),
then IC701 is suspect. Otherwise,
Woo+, Woo- IC702
CEN+, CEN-, Woo+, Woo- IC703
FR+, FR-, RR+, RR- IC704
4. Check the Via Hole Resister Value of IC GVDD Pins. GVDD Pins are Pin1 (GVDD_B),
Pin22 (GVDD_C), Pin23 (GVDD_D) and Pin44 (GVDD_A).
5. If you find to open the Via Hole, connect with wire about open the Via Hole.
Service Hint (Any Picture / Remark)
Measuse the resister value of AMP IC
GVDD Pins Via Hole.
Multimeter Range : (Resister Value)
Nornal Value : 1~2 (Approximate
value is short)
(For example 107K is abnormal
value)
One Point Repair Instruction
No. : AV-HT-2010-06
TI AMP IC701 ~ 704 (GVDD Pin Check Point)
Check the Via Hole Resister Value of IC GVDD Pins.
GVDD Pins are Pin1 (GVDD_B), Pin22 (GVDD_C), Pin23 (GVDD_D)
and Pin44 (GVDD_A).
One Point Repair Instruction
No. : AV-HT-2010-06
TI AMP IC701 (GVDD Pin Check Point) (FL+, FL-, RL+, RL-)
Soldering Point
PIN 44 PIN 23
Connect by wire
PIN 1 PIN 22
PIN 23
PIN 44
PIN 22
PIN 1
One Point Repair Instruction
No. : AV-HT-2010-06
TI AMP IC702 (GVDD Pin Check Point) (W+, W-)
PIN 23
Soldering Point
Connect by wire
PIN 22
PIN 23
PIN 22
One Point Repair Instruction
No. : AV-HT-2010-06
TI AMP IC703 (GVDD Pin Check Point) (W+, W-, C+, C-)
PIN 44
Soldering Point PIN 23
Connect by wire
PIN 1 PIN 22
PIN 23
PIN 44
PIN 1
PIN 22
One Point Repair Instruction
No. : AV-HT-2010-06
TI AMP IC704 (GVDD Pin Check Point) (FR+, FR-, RR+, RR-)
PIN 44 PIN 23
Connect by wire
PIN 1 PIN 22
PIN 44
PIN 23
PIN 1
PIN 22