PHILIPS - 32PF5320 28 Service Mode, Error Codes and Fault Finding Cont:-

Philips 32PF 5320  Service Mode, Error Codes & Fault Finding [Cont:]

NO PICTURE, BLANK SCREEN WITH CORRECT SOUND OUTPUT.

1. Check whether the user menu is visible.
2. If the user menu is OK, activate teletext mode.
3. If teletext is OK, the problem is in the ADC [B18]&[Columbus 3D combfilter [B19], if present [depending on model].
4. If the user menu is not visible, check the LCD panel back light is ON.
5. If the back light is OFF, the problem is in the power supply board or LCD panel.  Also check pin 12 (Lamp_ON_OFF) of 1J02.  It should be high, during normal operation.

Fault finding purposes, it is important know the following:-  

In Pixels Plus and Digital Crystal Clear models, which have an ADC [Analogue to Digital Converter] (B18), and Columbus 3D comb filter (B19), the digital input of the scaler is used for digital video path (Hercules output), whereas the analogue RGB output , analogue input of scaler, is only used for teletext.  This means that, no mixed mode [video plus teletext simultaneously] is possible.  If there is sound and teletext, but no video and user menu, the digital path [Hercules-ADC-Columbus-scaler] is faulty.  If there is sound, but no teletext, the back end part (Scaler-LCD panel] is faulty.  In crystal clear models, which do not have and ADC and Columbus, the RGB path (analogue input of scaler) is used for both video and teletext.

NO TV _ PC IS PRESENT

• Check the Hsync_SDTV and Vsync_SDTV are present at pin 1 & pin 13 of 7E03.
• If they are present, check teletext output.
• If there is no teletext output, the IC TDA 150XX may be the defect.

POWER SUPPLY

Check Fuse. The power supply contain one fuse near the AC input connector X002.

1. Check the power supply in OFF state by means of ohmic measurement.
2. Fuse may open in case of severe lightning strikes and/or failures in the power supply.
3. Check the Standby signal at pin 10 of X200.  On is High, Off is Low.  During standby mode, only 3.3V is present at pin 10.

PRECAUTIONS ON POWER SUPPLY BOARD.

• 12V Output (Pin 8 of X200): Short circuit protected by 2.5 Amps fuse X610. Over voltage protection when output voltage is more than 40% above nominal value.
• V audio output(+18V or +24V, depending power supply model used); (Pin 1 of X200): Short-circuit proof(+18 V version has 2.5 Amps fuse X660).  Over voltage protection when output voltage is more than 40% above nominal value.
• 3V3 Standby output (pin 3&4 of X200):  Short circuit proof with auto restart.  Over voltage protection when output voltage is more than 40% above nominal value.
• 24V output (for inverter X520 & X530);  Short-circuit proof, auto restart.  Over voltage protection when output voltage is more than 40% above nominal value.

STANDBY MODE

• Apply a 12 Ohm load  resistor of sufficient power rating to all outputs mentioned above [+12V,+18/24V, +3.3V and +24V].  Connect standby pin (pin 10 of X200) to Logical "L" (Low), ie to ground.  
• Over an input voltage range of 90VAC to 276VAC, only the +3.3V standby output shall be up.

NORMAL MODE

1. Apply a 12 Ohm load resistor of sufficient power rating to all output mentioned as above. Connect the standby pin to Logical High, ie, to 3.3V via a 2.3kohms pull up resistor.  
2. Over an input voltage range of 90VAC to 276VAC, all outputs shall be up.  The voltage on the +3V3 standby output shall be 3.3V over the entire input voltage range.  The voltage on the big 400V capacitor on the power supply should also be 400V +/-10%.