Marantz CD6005 - Display Troubleshooting; FL Tube Not Lighting

2. FLD
2.1. FL TUBE dosen't light
YES
YES
YES
NO
NO
NO
NO
YES
NO
Is the CUP12551 MAIN B'D
VP output voltage (+25V)
normal?
• FCC300 15pin (VP)
Is the CUP12551 MAIN
B'D +3.3V_Doutput voltage
(+3.3V) normal?
• FCC300 18pin (+3.3v)
Is the CUP12551 MAIN B'D lament output voltage
(AC3.6V) normal?
• FCC300 16pin(FIP2) - 13pin(FIP1)
Is the FLD (U4003) control waveform of the
CUP12552Z_A-4 FRONT B'D normal?
• 35pin(DIS_SO)
• 36pin(DIS_SCL)
• 37pin(DIS_CS)
• 38pin(DIS_RESET)
(For details of the control waveform, see
"2.2. FLD
Control Waveform"
.)
Check the voltage between the secondary side 1pin – 2pin of
the CUP12552Z_A-1 TRANS B'D Main Trans (T3951), and
replace the Main Trans (T3951) if any abnormalities are found.
FL TUBE
dosen't light.
Is the input voltage (+49.3V) of
the CUP12552Z_A-3 POWER
B'D transistor collector normal?
• Q3901
Check the input side circuit and
soldering of the transistor (Q3901),
and replace any faulty parts.
Is the regulator input voltage
(+5.13V) of the CUP12552Z_
A-3 POWER B'D normal?
• U3901
Is the regulator input voltage
(+7.14V) of the CUP12552Z_
A-3 POWER B'D normal?
• U3902
Is the regulator input voltage
(+9.22V) of the CUP12552Z_
A-3 POWER B'D normal?
• U3905
Check the input side circuit and
soldering of the transistor (D3932),
and replace any faulty parts.
Are the CUP12551 MAIN
B'D resistance (R308),
CUP12552Z_A-3 POWER B'D
resistance (R3912, R3915) and
diode (D3933) parts normal?
Signal Line from the CUP12551 MAIN B'D UCOM
• Check the soldering of the U2002 58pin(DIS_RESET),
59pin(DIS_CS), 60pin(DIS_SO), 61pin(DIS_SCL) and
surrounding circuits. Replace the UCOM if any abnormalities
are found.
• U2002
Check the circuit and soldering of
the transistor (Q3901) and output
load, and replace any faulty parts.
Check the circuit and soldering of
the regulator (U3901) and output
load, and replace any faulty parts.
Check the circuit and soldering of
the regulator (U3902) and output
load, and replace any faulty parts.
Check the circuit and soldering of
the regulator (U3905) and output
load, and replace any faulty parts.
NO
NO
NO
NO
YES
YES
YES
YES
Check the condition and soldering of the FLD (U4003) of the
CUP12552Z_A-4 FRONT B'D.
Replace the FLD if any abnormalities are found.
Check the condition and soldering
of the parts, and replace any
faulty parts.
NO
YES
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