Symptom: The backlights will flash on for seconds.
The bad caps (bulging tops) in the power supply were replaced as a set.
The 24V, 5V and all the signals are present after new caps are replaced.
The 24v and the BL_ON are shown up at the inverter board but it still just does the 2-seconds to black. Used a set of test lamps and it still blacks out.
So I heated up the 10 caps (100uF 35V) on the inverter board with hair dryer, the backlights then stay on.
Removed all 10 caps and check the capacitance, all are within 20%, check ESR with my home made ESR meter, 4 of them has >10 Ohms. I heated them up with hair dryer, then the ESR dropped down to 0.1 Ohm.
The bad caps (bulging tops) in the power supply were replaced as a set.
The 24V, 5V and all the signals are present after new caps are replaced.
The 24v and the BL_ON are shown up at the inverter board but it still just does the 2-seconds to black. Used a set of test lamps and it still blacks out.
So I heated up the 10 caps (100uF 35V) on the inverter board with hair dryer, the backlights then stay on.
Removed all 10 caps and check the capacitance, all are within 20%, check ESR with my home made ESR meter, 4 of them has >10 Ohms. I heated them up with hair dryer, then the ESR dropped down to 0.1 Ohm.
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