SHORT ON +3VLCD_CON (NO +3V) - HP COMPAQ G61

[vettouch]

Please, see attached schematic and help me find solution to this HP COMPAQ G61, which has no display on both LCD and CRT. Thank you.

Link to schematic - https://www.badcaps.net/forum/troubl...diagram-needed

[mon2]

Remove all power. Meter in resistance mode.

What is the exact resistance to ground of +3VLCD_CON?

Disconnect the LCD. Repeat the testing. Did the resistance change to a normal range? Post all measurements.

[vettouch]

mon2 Resistance to ground of +3VLCD_CON;

with LCD connected: @20 ohm meter range - 984; @20K ohm meter range - 4.80; @200K ohm meter range - 5.2; @2000K ohm meter range - 003;
with LCD disconnected: no reading for all meter ranges. Thanks

[mon2]

Are you sure the logic board is booted? If you attach a USB mouse, do you see the light flickering?

[vettouch]

mon2; the board comes on with fan spinning, but no activity with a USB mouse or keyboard attached.

[mcplslg123]

Display will come only when mb is posting. Since mb is not posting(as no usb activity),its futile to probe display connector voltages.

Instead focus on troubleshooting . Are all the voltages present on coil?

[vettouch]

@mcplslg123; Most coils have their voltages except one 1R5 coil, which was supposed to have 1.5v or so but had a very weird 58.6v when probed with a multimetre. The said coil is close to RAM connector.

[vettouch]

See the board

[mon2]

The voltage is very disturbing and does not make sense. Would the batteries be fresh on your meter? Nothing on the board is capable of spiking to such a voltage, even if we want it to.