zainka
Full Member level 2
Hi
I have an MultiQ MQ158e 15" VGA monitor which currently do not work.
- So far I have tried to do some measurements hoping that my problem was related to the power source. These monitors have a separat power adapter which feeds the monitor with 12V DC up to 3.5Amps. This is working ok.
- When the the case is opened one will find four PCBs. The power is connected to the main PCB and one is able to identify the regulators, the VGA inlet and an TDA8752 tripple ADC digitalizing the RGB signal, and one can also find the main DSP, the Video processor and some more. The user interface PCB is connected to the main board via a cable with 4 buttons which is '-' '+' 'select' and 'power'. The power button has a built in LED.
- When power is connected I can measure that the 5V regulator and 3,3V regulators are working, i.e. the board seems to be powered correctly. This is regardless to if i press the power button or not. If I press the power button the LED will not lighten. I have tested the LED and found it to be OK. I can also measure that both the video processor and the ADC is powered regardless of me pressing the power button or not after I have inserted the power cable to the monitor.
- I can also measure that if I press the power button it will alter the voltage on the corresponding pin on the connector where the cable between the power PCB and main PCB is inserted. This is normally 5V and goes to 0V when button is pressed. I believe this is correct behavior. There is also an resistor which I can identify to be the pull up for the power button which is connected to the regulated 5V.
Question is related to the fact that I do not know what to do next to make the monitor working again. I believe that the monitor is in some kind of suspend mode when power cable is plugged in and that the power button is used to signaling to the main processor (video processor i believe) to leave or enter suspend mode. I also believe the error is in the signaling path somewhere.
If anyone of you have some experience with this monitor, being anything, please leave a message. And, yes, a service manual would be nice to
Ah, one more thing, except for my measurements, the monitors appear as being completely dead.
I have an MultiQ MQ158e 15" VGA monitor which currently do not work.
- So far I have tried to do some measurements hoping that my problem was related to the power source. These monitors have a separat power adapter which feeds the monitor with 12V DC up to 3.5Amps. This is working ok.
- When the the case is opened one will find four PCBs. The power is connected to the main PCB and one is able to identify the regulators, the VGA inlet and an TDA8752 tripple ADC digitalizing the RGB signal, and one can also find the main DSP, the Video processor and some more. The user interface PCB is connected to the main board via a cable with 4 buttons which is '-' '+' 'select' and 'power'. The power button has a built in LED.
- When power is connected I can measure that the 5V regulator and 3,3V regulators are working, i.e. the board seems to be powered correctly. This is regardless to if i press the power button or not. If I press the power button the LED will not lighten. I have tested the LED and found it to be OK. I can also measure that both the video processor and the ADC is powered regardless of me pressing the power button or not after I have inserted the power cable to the monitor.
- I can also measure that if I press the power button it will alter the voltage on the corresponding pin on the connector where the cable between the power PCB and main PCB is inserted. This is normally 5V and goes to 0V when button is pressed. I believe this is correct behavior. There is also an resistor which I can identify to be the pull up for the power button which is connected to the regulated 5V.
Question is related to the fact that I do not know what to do next to make the monitor working again. I believe that the monitor is in some kind of suspend mode when power cable is plugged in and that the power button is used to signaling to the main processor (video processor i believe) to leave or enter suspend mode. I also believe the error is in the signaling path somewhere.
If anyone of you have some experience with this monitor, being anything, please leave a message. And, yes, a service manual would be nice to
Ah, one more thing, except for my measurements, the monitors appear as being completely dead.