when i turn on, Philliips TV is not on

[Nish]

Re: when i turn on, Philliips TV is not on

I donot know

[Nish]

Re: when i turn on, Philliips TV is not on

That's what I thought

[R_J]

Re: when i turn on, Philliips TV is not on

I have 5v from IC901 to ZD907

So you think that just because you have 5 volts on ZD907 you should have 5 volts for to supply the main board? Have another look at the schematic.
in post #50 you said:

I did, standby light blinking. I measure standby voltage. It becomes 1.8v not 4.48v.

Where is this voltage coming from???????

[Nish]

Re: when i turn on, Philliips TV is not on

I have 5v from IC901 to ZD907

[Nish]

Re: when i turn on, Philliips TV is not on

So do you have the standby +5 volts?

I donot have 5V at C951A

[R_J]

Re: when i turn on, Philliips TV is not on

I solder 2 wire at C915A and measure.

Now I removed from tv and measuring the voltage at C915A.

So do you have the standby +5 volts?

[Nish]

Re: when i turn on, Philliips TV is not on

from post #41 So you never did have this voltage?

I had this voltage before I put it in tv and connected t mainboard. After this now I do not have it.

Also: Where is this voltage coming from if you do not have standby voltage?

I solder 2 wire at C915A and measure.

Now I removed from tv and measuring the voltage at C915A.

[R_J]

Re: when i turn on, Philliips TV is not on

from post #41

Also when I fallow your drawing i got 5V

So you never did have this voltage?

Also:

I did, standby light blinking. I measure standby voltage. It becomes 1.8v not 4.48v.

Where is this voltage coming from if you do not have standby voltage?

[Nish]

Re: when i turn on, Philliips TV is not on

So NOW you don't have the standby AL5V any more?

No I don't have the standby voltage at C951A. But I have 5v at ZD907

[R_J]

Re: when i turn on, Philliips TV is not on

So NOW you don't have the standby AL5V any more?

[Nish]

Re: when i turn on, Philliips TV is not on

That could mean one of two things, there is a problem on the main board killing the 5 volts or the power supply can't supply enough current.
Is that measuring the standby voltage from ground to CN2 pin9 or across +&- of C951A. You could also check the standby voltage between pin9 and 11 on CN2
The AL+5V feeds 2 voltage regulators IC3601(+1.25v) and IC3606(+3.3v) (page37) maybe one of them is bad?
The one ic supplies 450ma and the other 200ma, so the power supply should be able to supply at least 1 amp. So you can try placing a 10Ω 2~5 watt resistor across the standby supply (or across C951A) This will draw about 500ma. and should not drop the 5 volts. If it does drop, then the power supply is at fault.

Sorry to say I have only 0 017v at C951A, before I solder the resistor.

[R_J]

Re: when i turn on, Philliips TV is not on

That could mean one of two things, there is a problem on the main board killing the 5 volts or the power supply can't supply enough current.
Is that measuring the standby voltage from ground to CN2 pin9 or across +&- of C951A. You could also check the standby voltage between pin9 and 11 on CN2
The AL+5V feeds 2 voltage regulators IC3601(+1.25v) and IC3606(+3.3v) (page37) maybe one of them is bad?
The one ic supplies 450ma and the other 200ma, so the power supply should be able to supply at least 1 amp. So you can try placing a 10Ω 2~5 watt resistor across the standby supply (or across C951A) This will draw about 500ma. and should not drop the 5 volts. If it does drop, then the power supply is at fault.

[Nish]

Re: when i turn on, Philliips TV is not on

Since you now have the AL+5V, why not install it in the tv and see if it works?

I did, standby light blinking. I measure standby voltage. It becomes 1.8v not 4.48v.

[R_J]

Re: when i turn on, Philliips TV is not on

Since you now have the AL+5V, why not install it in the tv and see if it works?

[Nish]

Re: when i turn on, Philliips TV is not on

What are you using for ground when you measure this voltage? Q905 emitter is connected to ground so use it to check the voltages in that area. AGAIN, the AL+5V does NOT use the same ground as the rest of the circuit. so stop using C951A as ground.

If you want the AL+5V or C951A to have the same ground you need to connect pin 11 to pin 5,6,7,8 Or add the jumper wire J14 next to CN2, Just remember to remove J14 after testing the power supply.

Sorry about it. I have 0V around that are.

[R_J]

Re: when i turn on, Philliips TV is not on

What are you using for ground when you measure this voltage? Q905 emitter is connected to ground so use it to check the voltages in that area. AGAIN, the AL+5V does NOT use the same ground as the rest of the circuit. so stop using C951A as ground.

If you want the AL+5V or C951A to have the same ground you need to connect pin 11 to pin 5,6,7,8 Or add the jumper wire J14 next to CN2, Just remember to remove J14 after testing the power supply.

[Nish]

Re: when i turn on, Philliips TV is not on

I want to remove the Q905, but I have still 4.48. While i unsolder it wonot effect any other parts.

[Nish]

Re: when i turn on, Philliips TV is not on

Q910, Q905 all 3 pin has 4.48v.

[Nish]

Re: when i turn on, Philliips TV is not on

The voltage that supplies PC902 comes from the AL+5V and connects to Q910 emitter. Q910 must be switched on by Q905 to supply the AL+5V to the collector and then to PC902, pin1

This Philips POS service manual sucks and blows. If you look CN2 on Page 43, then look at page 42 CN3002 (this is where they connect together) it gets even more confusing. They swap the wires around so maybe pin 11(5vground) connects to the 12v ground at the main board?

Yes it is confusing. I measured voltage Q910, Q905 has 4.48v and PC902 pin1 and 2 has 4.48v. Something short or I am using wrong ground. I am using negative lead of C951A as my ground.

[R_J]

Re: when i turn on, Philliips TV is not on

The voltage that supplies PC902 comes from the AL+5V and connects to Q910 emitter. Q910 must be switched on by Q905 to supply the AL+5V to the collector and then to PC902, pin1

This Philips POS service manual sucks and blows. If you look CN2 on Page 43, then look at page 42 CN3002 (this is where they connect together) it gets even more confusing. They swap the wires around so maybe pin 11(5vground) connects to the 12v ground at the main board?