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Service Guide OL400
Chapter 4 Failure & Repair Analysis
RAP 01Printer Does Not Initialize
START
Turn the power OFF, then ON.
Is the WARMING UP message displayed?
YES
Go to B
NO
Check the AC cable connection.
Verify that +5V output is generated. Check the connection at the main controller circuit board
CN1-1 (+5V) and CN1-3 (0V)
YES
Go to A
NO
Is the power fuse open?
YES
Check for shorts between AC and replace the fuse
NO
Is power generated when the engine controller circuit board is detached
(from the power supply unit) and AC power is turned ON?
YES
Is there a short b38V and 0V? Is there a short between
+5V and 0V when the engine controller board is installed. (Make this
check on the engine controller board.) Be sure that the circuit side of the
engine controller board is not touching the shield frame.
NO
Replace the power supply unit.
YES
Install Engine Controller Board correctly.
A
Is the Block Character displayed on the operator panel 16 seconds after the power is turned ON?
YES
Replace the main controller circuit board or the engine controller circuit board.
NO
Is the operator panel cable disconnected?
YES
Connect the cable.
NO
Replace the operator panel board.