IBM R50e schematics

[rtstorm]

Re: IBM R50e schematics

i replace again U42 but still nothing, no sign of life. Please what to check next, this is older laptop maybe mains doesnt go over this IC?

On U41 i have only 16V on pin 22 (V+), all other pin is 0V.

[rtstorm]

Re: IBM R50e schematics

please take a look at page 69. I have 16V on Q2 and Q6 pins 7 and 8. All other pin is 0V. How is this controlled?

[rtstorm]

Re: IBM R50e schematics

i suspect at U41 (MAX 1631AEAI). It has only 16V on pin 22 (V+) and nothing else. As i figured this U41 need to send VCC3M and VCC5M to H8S (U23) and TSURUMAI (U61) but it doesn't.

Am i thinking in the right way?

[rtstorm]

Re: IBM R50e schematics

hi, i replace U41 but still no power. I am going crazy, is this TSURUMAI (U61) fail? I do not understand this king of fail.

Please help

[rtstorm]

Re: IBM R50e schematics

hi, i replace U61 (TSURUMAI) no help please any idea?

[atsio]

Re: IBM R50e schematics

What is the voltage on pin 4 of Q34 and Q36? Give also resistance to ground without power supply connected on pins 1,4,8 of Q34 and Q36.

[rtstorm]

Re: IBM R50e schematics

Q34 pin 4 - 2.85V
Q36 pin 4 - 10.40V

Q34 pin 1 - GND = 0.6Mohm
Q34 pin 4 - GND = 1.1Mohm
Q34 pin 8 - GND = 201kOhm

Q36 pin 1 - GND = 201kOhm
Q36 pin 4 - GND = 1.2Mohm
Q36 pin 8 - GND = 24MOhm

[atsio]

Re: IBM R50e schematics

What is the voltage on pins 1 and 3 of Q32 and resistance to ground without power supply on those pins and all the pins of U42?

[rtstorm]

Re: IBM R50e schematics

Q32 pin1 - 0.19V
Q32 pin 3 - 0V

Q32 pin 1 - GND = 39kOhm
Q32 pin 3 - GND = 39kOhm

U42:
pin1 - 24Mohm
pin2 - 116kOhm
pin3 - 201kOhm
pin4 - 38.7kOhm
pin5 - 10.8kOhm
pin6 - 22MOhm
pin7 - 2.2Ohm
pin8 - 16.7kOhm
pin9 - 33kOhm
pin10 - 9.7kOhm
pin11 - 35Mohm
pin12 - no connection to GND (0)
pin13 - 2.4Ohm
pin14 - 11.3Mohm
pin15 - 16.7kOhm
pin16 - 10.8kOhm
pin17 - 10.5MOhm
pin18 - 11.5MOhm
pin19 - 2.2ohm
pin20 - 7.8MOhm
pin21 - 30kOhm
pin22 - no connection to GND (0)
pin23 - no connection to GND (0)
pin24 - 10.8MOhm

[atsio]

Re: IBM R50e schematics

Check voltages on pins 57,34, 55, 52, 54, 10, 11, 44, 58, 59 of U61

[rtstorm]

Re: IBM R50e schematics

U61:
pin57 - when measuring voltage grow from 0V to 3.19V stable at 3.19V
pin34 - 3.21V
pin55 - 0V
pin52 - 4.2V
pin54 - 1V
pin10 - 0.2V
pin11 - 0.24V
pin44 - 0V
pin58 - 0V
pin59 - 0V

[atsio]

Re: IBM R50e schematics

Check voltage and resistance to ground (with out power supply) on all three pins of D10, D19, D23. Check if diodes are ok.

[rtstorm]

Re: IBM R50e schematics

D10
pin1 - -4.4V
pin2 - -4.4V
pin4 - 3V

pin1 - 280kOhm
pin2 - 277kOhm
pin3 - 176kOhm

diode test OK

D19

pin1 - 2.5V
pin2 - 2.5V
pin4 - 2V

pin1 - 270kOhm
pin2 - 270kOhm
pin3 - 170kOhm

diode test OK

D23 - i do not have it on my board, that spot is empty.

[atsio]

Re: IBM R50e schematics

Did you had the battery connected while you were taking measurements of voltages?

[atsio]

Re: IBM R50e schematics

Check voltages on all pins of Q13 and on both sides of R422 and R453.

[dj_ricoh]

Re: IBM R50e schematics

i think there is something shorted to ground !
like a cap!
and lift the L5 coil

[dj_ricoh]

Re: IBM R50e schematics

see pin 24 on U42 10Mohms. pff
go to q4 and that coil

[atsio]

Re: IBM R50e schematics

i think there is something shorted to ground !
like a cap!
and lift the L5 coil

What? When all resistances measure allright.

[rtstorm]

Re: IBM R50e schematics

@ atsio

Q13
pin1 - 2.99V
pin2 - 2.89V
pin3 - 2.89V
pin4 - 1.2V
pin5 - 15.96V
pin6 - 15.96V
pin7 - 15.96V
pin8 - 15.96V

R422 i cannot find (KODIAK program wont display it)
R453 one side is 16.3V and other side is -7.8V

I did not use the battery while i was testing.

[rtstorm]

Re: IBM R50e schematics

see pin 24 on U42 10Mohms. pff
go to q4 and that coil

Q4
pin1 - 0.3V
pin2 - 0.56V
pin3 - 0V
pin4 - 0V
pin5 - 0.3V
pin6 - 0.3V
pin7 - 16V
pin8 - 16V

L5 coil have 0.3V on both side