Philips TV suddenly won't turn on

[MatiB]

My TV doesn't turn on, not even the standby red LED. When I plug it, it first makes a continuous noise before it starts making a "clicking" noise. The controller and side buttons don't do anything. The model is Philips 32PFL4007D/77. I've checked all capacitors and they are ok. Also, the 5, 12 and 24 volts lines are all producing the correct voltage. The sound comes from the power supply board, and not from the speakers. I would appreciate any help with this, thanks.

[BMack]

Check the cost on a replacement main board.

[MatiB]

You need to be more specific about just how you checked all the capacitors. Some (not saying you) just look to see they are not bulging and think that is a proper check. If they are bulging they are bad but if they are not bulging you still can't be sure they are good.

Hi, I've only checked if they are bulging or if they aren't properly soldered or came loose. What else could I try to make sure they are ok?
In some questions I've seen online, people sugested checking the capacitors because they could prevent the power supply board from generating enough power, if any at all, and cause the main board to attempt to continually reset the power supply and cause the clicking noise.

Check the cost on a replacement main board.

Changing the board could be a solution, although an expensive one. The only problem is that I don't know if the problem is in the main board or the power supply board.
If anyone knows what else I could check to narrow the problem it would be great

[james_s]

Electrolytic capacitors often fail without any visible signs, you really need an ESR meter to check them. Lacking that, the shotgun approach of just replacing all of them is a viable option. I would first check the power supply, are the outputs labeled?

[MatiB]

Electrolytic capacitors often fail without any visible signs, you really need an ESR meter to check them. Lacking that, the shotgun approach of just replacing all of them is a viable option. I would first check the power supply, are the outputs labeled?

I don't have an ESR meter, is there any other test I could make?
The power supply outputs to the mainboard, and the cable is labeled. It has 5v, 12v, 24v, GND, PS_ON, P_OK, ON/OFF. When I checked with the multimeter all the voltages were ok, although slightely lower (like 200mV).

[james_s]

That suggests that the power supply is ok. You could look on ebay for a new main board, sometimes you can find them cheap from TVs with a broken panel. It can be really hard to troubleshoot these things at a component level because they're so tightly integrated and virtually no service information is available.

[Armadillo]

Electrolytic capacitors often fail without any visible signs, you really need an ESR meter to check them. Lacking that, the shotgun approach of just replacing all of them is a viable option. I would first check the power supply, are the outputs labeled?

I don't have an ESR meter, is there any other test I could make?
The power supply outputs to the mainboard, and the cable is labeled. It has 5v, 12v, 24v, GND, PS_ON, P_OK, ON/OFF. When I checked with the multimeter all the voltages were ok, although slightely lower (like 200mV).

Is the P-ON+21V line voltage normal?
Check if there is any leak or short-circuiting on the primary circuit component, and service it if defective.
(D601, D602, D603, D604, Q601, Q602, T601)