The manual was complete and extremely helpful in both diagnosing the problem I was having as well as fixing it. Excellent quality. I will getting additional manuals in the future.
Exactly the JVC service manual and schematics that I was looking for - delivered just hours after order. Will do business again!
Text excerpt from page 54 (click to view)
3-2. Switch Settings on the CPU-246 Board and LEDs Description
Other areas of the LED These LEDs indicate the operation stasus of the SUB CPU and the memory. D0 : Lights : Flash memory (IC136 on the CPU-246 board) of the SUB CPU is damaged. Lights off : Flash memory (IC136 on the CPU-246 board) of the SUB CPU is normal. D1 : Lights : Flash memory (IC136 on the CPU-246 board) of the SUB CPU is empty. Lights off : Flash memory (IC136 on the CPU-246 board) of the SUB CPU is normal. D2 : Lights :
The ROM (IC138 on the CPU-246 board), RAM (IC137 on the CPU-246 board) or dual port RAMs (IC134 or IC135 on the CPU-246 board) of the SUB CPU is abnormal. Light off : The ROM (IC138 on the CPU-246 board), RAM (IC137 on the CPU-246 board) and dual port RAMs (IC134 or IC135 on the CPU-246 board) of the SUB CPU are normal. D3 : This LED lights when the system is running in SUB CPU flash memory access inhibit mode due to the S5 switch setting on the CPU-246 board. D102, D112 (M12) : These LEDs indicate the result of checking the operating condition of the main CPU. D295 (Green color) (R9) : POWER (+5V) Lights when the power is supplied to the CPU-246 board. D8 (Green color) (R9) : POWER (+12V) Lights when the power is supplied to the CPU-246 board.
