Need repair help with CP-RS55 Projector PSU

I have been working on this projector for a while now and its really stumping me!
This is what it started doing;
Turn on mains, blown fuse, bridge rectifier, MOSFET Q102, PNP Q103, Q104
R103, R104, R105, R106. Output pin 7 IC101 (FA5501)

Replaced all of these and tested using 12v-240v Inverter on current limit at 12v. Pulled 1A @12V off load.

Now we had no problems but we cant see IC102 working, I believe its a FA5508. No datasheet! So I looked and found it had same pin outs as FA5542. But we tested voltage on Vcc of IC102, found 20v. Looking at datasheet for FA5542 the 20v comes from the internals of the IC and is picked up from pin 8 (VH) This is a voltage enabling the Mosfet Q201 to get the transformer T201 to produce the voltages for the rest of the PSU. I am really stuck with this problem now as all the parts we replaced do not make the PSU work. We get no outputs from any of the 'cold side' OF T201

Attached is some datasheet for FA5542 (Closest I can find for FA5508)
Also screenshot of Schematics for PSU

Obviously the FA5501 (IC101) is not recieving Vcc as there is no 4.1v to pull up on/off pin of CN102 so the rectified mains is around 330v where it would be 370 if IC101 was working, the way I see it IC102 should power up first.

Thanks in advance for any help.

http://img10.imageshack.us/f/rs55psu.jpg/
http://www.fujielectric.com/device/semi/products/ic/ac_dc_green.html
Click on the FA5542 link pdf, near top page.

 

Try that sorry should have really checked, think you need to click the zoom button to see it well.

http://img10.imageshack.us/f/rs55psu.jpg/

 

Sorry we did replace Q101 and also Q102, I believe R102 was ok after we checked it. We tested both doides D102, D103 and were ok. The IC201 uses pin 8 (VH) to start the Mosfet Q201 switching. Without the IC201 working not even IC101 will work, as you can see by the opto couplers with out a 4.1v supply the Vcc to IC101 is not there. I am closely looking into why IC201 is not working, I think we have found this area to be where to look.

Also have checked to shorts on the T101 and measures 390uh, this is inline with the application notes on IC101.

My thoughts are now conditions around IC201are not as they should be, either the IC is in some sort of shut down mode, safe mode or has completly failed.

 

Some pictures of the board, as you can see we have had to repair some of the burnt tracks!

http://img340.imageshack.us/i/dsc00001bk.jpg/
http://img37.imageshack.us/i/dsc00002agt.jpg/
http://img29.imageshack.us/i/dsc00131sk.jpg/
http://img18.imageshack.us/i/dsc00140ns.jpg/

 

I will get the Zener looked at and also the resistor you mention, I will try to supply Vcc for IC101 externally to see if it will switch the fets and supply the 370v. At least that way we can focus on why IC201 is not working as it should do.

Here is the best I can do with getting the burnt tracks on the schematic's.

http://img207.imageshack.us/i/trackdamage.png/

 

Also if anyone can find a datasheet for FA5508 I would be very greatful!! I have looked everywhere!

 

Done some more fault finding, found datasheet for FA5518 which is equivilent of 5508. Measured voltages on PIN1 (CS) and gives reading of 8.7volts. Now reading the datasheet this indicates that the IC is in latch mode. Looking back at the schematics im thinking a condition on the CS pin is causing the latch.

Can anyone think of a idea what CS pin is doing? I know that PC202 are doing and I believe PR101 is a therminstor.

FA5518 Datasheet

http://www.megaupload.com/?d=B1L2IYBS

 

Just to let you all know, its now 100% working. Found the faults, the psu testing lead us to believe was still problems as was not under any load. Gave Vcc low and very noisy readings with no loads on the outputs!