Panasonic CF-74GCDADBM service manual Power-On Self Test Boot Check

5 Power-On Self Test (Boot Check)

Outline of POST

The set has a boot check function called POST (Power-On Self Test) in it. The condition of the main body is diagnosed by checking beep sound or error code.

zStart .............Test begins automatically when power switch is set to ON.

zNormal finish .....After memory checking, a beep sound is issued once and the set is placed into automatic stop. Note: If no error occurs, nothing is displayed. (No display of OK, etc.)

Error Diagnosis by Checking Beep Signal Sound

The beep sound is as follows:

(1 (long sound) -2-3-4) (Length of bar shows length of sound.)

= long sound (about 0.4 sec.), = short sound (about 0.2 sec.), Length between sounds is about 0.1 sec.

zTable of errors classified by beep sounds

Diagnosis	Beep signal sound	Error message
Main board	1(long sound)-2	BIOS ROM error
	1-2-2-3	BIOS ROM error
	1-3-1-1	RAM error
	1-3-1-3	Keyboard controller error
	1-3-4-1	RAM error
	1-3-4-3	RAM error
	1-4-1-1	RAM error
	2-1-2-3	BIOS ROM error
	2-2-3-1	Occurrence of unexpected offering

(Note) A beep sound is also issued in case of other I/O trouble.

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