Dell E173FP service manual PANEL-POWER Circuit, Inverter Control Relative Circuit

2) PANEL-POWER CIRCUIT

NG

Check R172 should have response from 0V to 5V When we switch the power switch from on to off

OK, R172 have response

NG, no

Measured the Q104 pin 3= 5 V?

OK

OK

3) INVERTER CONTROL RELATIVE CIRCUIT

DELL E173FP Service Manual

Check the PPWR panel power relative circuit, Q105, Q104 In normal operation, when LED =green, R172 should =5 v,

If PPWR no-response when the power switch

Turn on and turn off, replace the U102(GMZan3-SL)

Check U202 pin 4, 16, 28=3.3V?

Yes

Replace Q104 ( N-mos, AO3401)

Measured the inverter connector CN104 Pin1 on/off control=3.3V (on)

Pin2 PWM signal control dim 0V-5V

NG, still no screen

Replace Inverter board to new-one,

and Check the screen is normal??

OK

NG

NG

Check the Bklt-On relative circuit, R162, In normal operation, when LED =green, R162 Bklt-On should =3.3V,

If Bklt-On no-response when the power switch turn on-off, Replace U102 GMZan3-SL

Check NO SCREEN APPEAR block

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