JVC XV-521BK Service Manual page 18

XV-521BK/523GD/522SL
(4) Focus ON error
1. Is FE produced? → Pattern, IC101
2. Is FODRV signal produced? (R280) → Pattern, IC201
3. Is drive voltage available?
If not available: pattern, driver, or mechanism. (Turn the power OFF then measure the resistance between
CN101 "30" and "31".)
4. Defective mechanism
(5) Tracking ON error
1. When tracking loop is not retracted, TE waveform does not converge.
2. Defective mechanism
The possible cause for unavailability of correct retraction is that automatic adjustment cannot be made
successfully.
3. Driver and its related parts (IC271)
Constant and IC defects (When it was passed during the adjustment below without going into an abnormal
condition)
4. Servo IC (IC201)
When automatic adjustment was unsuccessful due to defective ICs.
(6) Spindle CLV error
1. When the spindle servo is not locked successfully, RF eye-pattern cannot be locked successfully.
2. IC101"35" (RF OUT), IC101"30" (RF-), IC101"31"(RF+)
3. Is the driver spindle signal input not clipped by the output signal?
4. Is the transistor ON?
5. Defective spindle motor or driver.
6. Other errors may be caused by defective mechanism (jitter) etc. in IC 101 and IC201.
(7) Address Read Failure
The failure may be caused by many possible factors and it is difficult to pick one out. However, the following
are among the possible causes.
1. Defective mechanism (significant jitter)
2. IC (IC201, IC301, IC401)
3. Contaminated or damaged discs.
(8) Inter-layer Jump error
1. Defective mechanism.
2. Defective constant or IC of the Driver IC (IC271).
3. Defective servo IC (IC201).
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