Chosen Solution
I have an HP 2509b monitor that is experiencing backlight failure. After turning the monitor on, the backlight turns on and then off shortly thereafter. I have replaced the CFLs (thinking they may be bad) and checked a power supply mosfet and diode one YouTuber recommended replacing. I have also visually checked the capacitors; they all look fine. Yet still, the problem remains. What could be causing this issue, and how may I go about fixing it from here? Thank you! Edit: Added photos of the power supply. The red wire was a fix of mine when a PCB trace came off with the MOSFET. (I removed it to test the MOSFET earlier in the repair).
Hi, things to try. Hold the menu button on the monitor for 10 seconds to see if you get a monitor ’locked’ or unlocked’ message appearing. if it says unlocked try changing your input source to a different input using the OSD if it stays on now. The input source detection should be auto but if the above works try to select a different input source type and then if you have got a choice of video outputs types available, i.e HDMI, DVI vga etc.try connecting each one in turn to your monitor to see if it is a faulty input type and whether it is also that the auto detect isn’t working.
The caps in the picture look good. Start testing the diodes and transistors (FET & BJT) and look for cold solder joints.
I have the same problem, same monitor (HP2509m), but in all the chatter above I find no solution. Was this ever resolved? Jayeff says to check voltages and Minho says to test diodes and transistors, but did any of that work? Andy why is this considered solved, and a “chosen solution”? I don’t see Jay Developer stating it worked.
Another thread said to use another temp monitor, then once your able to see inside your Windows desktop, install the “HP Display Assistant”. Then power down and reconnect the 2509 monitor. Upon rebooting, the HP Display Asst will fix it.
