Brand Model Chassis Keyword Symptom Cure
Proscan PS35682 CTC170 Audio CTC170 Unit has 1/4 second delay in the audio when changing from any channel to channel 7. The audio will delay 1/4 second in the SAP mode before switching to stereo. According to RCA this is normal due to the design of MTS circuitry. It must sample SAP briefly to determine it presence. The cust notices it because the SAP is a different audio source than all other channels.
Proscan PS52682 CTC171 Audio CTC171 unit has and audio defect when the level of audio is selected to minimum the sound will actually go to minimum sound. But when graphical display is moved up to two notches above minimum the audio blasts Defect indicates the D/A converter is causing the trouble. Since both channels are effected, U1601 204290 is the suspected component for this failure.
Proscan PS35682 CTC170 cycling on an off CTC170 chassis. Unit will cycle on and off three times then finally shut off. Gave tech instructions relating to the this type of shut down complaint. The 9 volt source was OK. The 3.7 volts that must be on pin 2 of U3101 (CPU) never rose above .8 volts. These two voltages are critical to the operation of the D.C. detect circuit. Problem was U1902 audio output IC on audio board.
Proscan PS35680 CTC170 cycling on an off Set may cycle on and off while the set is cool or it might do it when it is warm. This is usually accompanied with a termendous "Thump" in the speakers Close inspectiopn of CR3604 finds the diode lead wires heavely oxidized caused by a yellow glue that complete covers the diode. It is a small glass diode on the signal board next to R3608 the 1 ohm 10 watt resistor. It is recommended to replace it with a 146015 or a 1N4001. This is a plain general purpose silicon diode. You will need to completely remove the remaining glue from the CBA.
Proscan PS35682 CTC170 Dead CTC170 chassis. Basically dead. Unit will turn on and them immediately shut off again as soon as high voltage begins to rise. Had tech remove High Voltage input to HV distribution block, at the flyback, High voltage came up, and stayed on. Appears the HV block may very well be shorted. Tech replacing HV block
Proscan PS52682 CTC171 Dead CTC171 chassis Unit will not run. Does not have standby B+ R4051 open on main chassis for switch mode supply
PSN PS60682 CTC171 Dead Unit will not turn on. All standby voltages are normal. Monitoring the 143 vdc source finds the voltage dropping to 46 volts at turn on then cycles on and off 3 times then stops. Removing the Anode lead from the flyback transformer to the HV block assembly (being careful to position the lead wire from potentially arcing to anything). Power up the set and the high voltage returns and the set operates. Problem was the HV block. Note: There is a small black rubber grommet that comes loose and stays inside the HV block chimney. These must be fished out with a tool fabricated out of a paperclip. By straightening out the paper clip and taking one end an bending it 90 degrees. Trim the length of this bent end to 1/16 of a inch. Poke this end into the chimney of the defective HV block and pull out the grommet.
Proscan PS60682 CTC171 E/ W Pincushion PS60682 CTC171 Unit has server hour glass distortion Unit has shorted CR4402 an C4402
Proscan PS35682 CTC170 horizontal CTC170 Unit has symptom of horizontal ripple across screen. At times the set will shut off and turn back on with the statement about power interuption. Monitoring the Q3602 12 volt regulator I find the voltage very unstable when the time the horizontal instability exists. Q3601 in intermittently causing Q3602 to fall out of saturation by varying its base voltage. Q3501 & Q3502 are unstable causing a partial reset of the CPU and shutting off Q3602. Replaced Q3501, and Q3501 corrected problem.
Proscan PS35682 CTC171 horizontal RCA PS35882 Unit loosing Horizontal sync. Tech rep[laced the Horizontal retrace caps in the hopes of correcting the sync problem Reference pulse at U4350(3) was at 5 vpp and flyback comparison pules input to U4350(5) also normal. All indications point to an "out of adjustment R4310 or defective U4350.
Proscan PS35682 CTC170 horizontal CTC170 Unit has symptom of horizontal ripple across screen. At times the set will shut off and turn back on with the statement about power interruption. Monitoring the Q3602 12 volt regulator I find the voltage very unstable when the time the horizontal instability exists. Q3601 in intermittently causing Q3602 to fall out of saturation by varying its base voltage. Q3501 & Q3502 are unstable causing a partial reset of the CPU and shutting off Q3602. Replaced Q3501, and Q3501 corrected problem.
Proscan PS60682 CTC171 horizontal PS60682 insufficient horizontal sweep. Popping. High voltage lead in HV block is burned and needs to have the HV gasket replaced with the block.
Proscan PS35682 CTC171 horizontal RCA PS35882 Unit loosing Horizontal sync. Tech replaced the Horizontal retrace caps in the hopes of correcting the sync problem Reference pulse at U4350(3) was at 5 volts peak to peak and flyback comparison pulse input to U4350(5) also normal. All indications point to an "out of adjustment R4310 or defective U4350.
Proscan PS35682 CTC170 No raster CTC170. Unit has no raster but has sound. Previous tech ordered several parts relating to the PIP combfilter, and Jungle chip. These were not defective! The heat sinks in the PTV aux board were cold. None of the power handling devices had any voltages on them. It was discovered a short on the -15 volt rectifier on the PTV aux power supply.
Proscan PS35682 CTC170 No Raster RCA CTC170 PS35682. Unit does not have raster, sound, or On screen Display. Unit is missing the 12 volt supply at the emitter of Q3602. The foil land after the R3608 was damaged and not making solid connections to the Collector
Proscan PS35682 CTC170 No Raster RCA CTC170. Unit has no raster Unit has had the HV block replaced still has no video and OSD. Asked tech to feel the heatsinks of the convergence output and see if the are warm. All hearsinks are cold. A short was measured on the +15 volt output of the PTV Aux power supply rectifiers on the .
Proscan PS60682 CTC171 No Raster PS60682 CTC171 NO raster has sound. All heat sinks on the PTV Aux power supply & Convergence Amp transistors cold. PTV Aux power supply is not running. Had tech check the rectifiers in the PTV AUX Power supply. Tech found a shorted CR7059 in the +15 volt source.
Proscan PS60682 CTC171` No Raster PTK171 Unit has no raster. Has sound when PIP is invoked. Unit has trouble in the scan loss circuit. Scan loose is being triggered and causing the raster to mute. All other stand by voltages from the main supply are normal Had tech begin with verifying the power supply voltages from the secondary side of the PTV AUX board. It was discovered there is a short in the PTV AUX board and the +15 volt supply is shorted to ground. PTV AUX board is defective and needs replacement.
Proscan PS52682 CTC171 No turn on CTC171 Unit Will not turn on. Just a relay click, but nothing else. I had tech begin checking for loose connections on and around the SIP diode board. After checking the condition of the SIP board the set began to run.
Proscan PS35682 CTC170 No Turn On CTC170. Unit has high pitch chirp from the power supply.  Unit has no voltage at Pin 16 of U4100. Has short circuit at stand-by run supply. After isolating the loads from the IC chip it was discovered that CR4101 was leaky
Proscan PS35682 CTC170 No turn on Unit has high pitch chirp from the power supply in the stand by mode Unit has no voltage at Pin 16 of U4100. Has short circuit at stand-by run supply. After isolating the loads from the IC chip it was discovered that CR4101 was leaky
Proscan PS52682 CTC171 No turn on CTC171 Unit Will not turn on. Just a relay click, but nothing else. I had tech begin checking for loose connections on and around the SIP diode board. After checking the condition of the SIP board the set began to run.
Proscan PS60682 CTC171 No turn on RCA CTC171 chassis. Unit will not turn on. All stand by supplies are running 30% too high. Unit has defective CR4103 diode in stand by feedback circuit.
RCA PS35682 CTC170 OSD Tech claims he has this chassis with a weird microprocessor problem as you know the set can come on in any state with boxes funny looking designs or maybe come on normal but not to last for too long. Tech replaced CR 3602, Q3600, Q3607, Q3610, but still had the same problem. One thing that should be known on this chassis the Microprocessor does not generate the OSD. The Pixel Graphics module handles ALL of the OSD display activities. The television will operate without the Pixel Graphics module. You just simply will not have any OSD. I would be more concerned to what is happening to PGM module rather than the Main system control. Suggest trying the Pixel Graphics module first before IFS. Or see if the symptom shows up if you disconnect the module. Problem was caused by the Pixel Graphic Module
RCA PS35682 CTC170 OSD Tech claims he has this chassis with a weird microprocessor problem as you know the set can come on in any state with boxes funny looking designs or maybe come on normal but not to last for too long. Tech replaced CR 3602, Q3600, Q3607, Q3610, but still had the same problem. One thing that should be known on this chassis the Microprocessor does not generate the OSD. The Pixel Graphics module handles ALL of the OSD display activities. The television will operate without the Pixel Graphics module. You just simply will not have any OSD. I would be more concerned to what is happening to PGM module rather than the Main system control. Suggest trying the Pixel Graphics module first before IFS. Or see if the symptom shows up if you disconnect the module. Problem was caused by the Pixel Graphic Module.
Proscan PS35682 CTC170 Shut down CTC170 Unit shuts down Unit looses the horizontal drive Still has B+ at collector of Horizontal output. Appears unit is going into Xray shut down. The X-ray protection circuit appears to be malfunctioning in this unit. Defeating the X-ray restores normal operation. Had tech order the components in the X-ray latch circuit listed as a XRP kit replacement for CR4902.
Proscan PS35682 CTC170 Shut down CTC170. Iintermittent symptom of intermittent shutoff. . It was determined that the new sip module was not soldered correctly.
Proscan PS60682 CTC171 Shut down RCA CTC171 Unit will shut off and give the statement "Unit has experienced a power failurre" SIP module, C4116, C4117 on the 16 and 7.5 volt supply line were replaced. The statement mean the set got a hard reset. Tech needs to check into the B+ at the output of the SMPS power supply. Power supply was stable but the 12 and 5 volt run supplies kept shutting off. These are switched by the microprocessor and the reset transistors. Q3502 was leaky.
Proscan PS35682 CTC170 Shut down CTC170 chassis Unit will turn on but shut down and cycle 3 times. The 12 volts supply intermittently disappears from the After 3 hours total working on chassis it was found the 26 volt source was the reason of the fault caused by a fractured FB2409 in the Progressive scan processor causing the loss of the 2h horizontal signal. It is recommended to remove and jump the FB2409. On newer models this ferrite bead is not used. Just a jumper wire.
Proscan PS35682 CTC170 Shut down CTC170 chassis. Unit shuts down. Had tech check the supply of the 140 VDU. Supply in stand by is running at 85 vdc. However the rest of the secondary voltages do not appear too low. This would indicate trouble with the 140 VDC source rectifier CR4050 or filter capacitor C4050. Unit had defective CR4050.
Proscan PS35682 CTC170 Shut down CTC170 unit has a shut down symptom. The would run for several hours before but now shuts down almost immediately Tech needed confirmation of the Z-match Circuit board part number and voltages on output side. Discovered small burnt spot in CBA material. Tech needs CBA and HV block. Because of the burn on the board it will not be repairable.
Proscan PS35682 CTC170 Shut down CTC170 Unit shuts down Unit looses the horizontal drive Still has B+ at collector of Horizontal output. Appears unit is going into X-ray shut down. The X-ray protection circuit appears to be malfunctioning in this unit. Defeating the X-ray restores normal operation. Had tech order the components in the X-ray latch circuit listed as a XRP kit replacement for CR4902.
Proscan PS35682 CTC170 Shut down CtC170 Will intermittently go to shut down then back on again Unit appears to be going into Xray protection shutdown. CR4901 running 27 volts. Original call was a customer complaint of insufficient horizontal sweep. Tech corrected the fault by adjusting the width control. This was a mistake because it masked another problem . Either C4401 ir C4402 had decreased in value causing the high voltage to increase the reduce the sweep. Replacing the two capacitors & readjusting the width corrected the trouble.
Proscan PS35682 CTC170 Shut down CTC170. Intermittent symptom of intermittent shutoff. . It was determined that the new sip module was not soldered correctly.
Proscan PS35680 CTC170 Shut down RCA CTC170 chassis Unit will shut down when the deflection or Diode SIP board is tapped on. All other voltages at the secondary of the Power supply were normal. I had tech monitor the collector of the Horizontal driver transistor Q4301. The B+ was Zero volts. Tracing back to the 16 volt source it was found a bad trace the connected R4300 to the 16 volt source. Apparently an aluminum twist tab for a heat sink was twisted the wrong direction during assembly and the trace was torn. Hard wire trace corrected the symptom.
Proscan PS35682 CTC170 Shut down RCA CTC170 chassis Unit will shut down when the deflection or Diode SIP board is tapped on. All other voltages at the secondary of the Power supply were normal.  I had tech monitor the collector of the Horizontal driver transistor Q4301. The B+ was Zero volts. Tracing back to the 16 volt source it was found a bad trace the connected R4300 to the 16 volt source. Apparently an aluminum twist tab for a heat sink was twisted the wrong direction during assembly and the trace was torn. Hard wire trace corrected the symptom.
Proscan PS35682 CTC170 Shut down RCA CTC170 Unit will shut down when deflection board is touched No B+ to Q4302. Caused by open connection from R4300
Proscan PS52682 CTC171 Shut down CTC171 125 class. Unit will run in standby mode but shut down when the set is turned on Monitoring the B+ the 140 volt source jumps to 185 vdc. The set will execute the X-ray protection circuit instantly. R4148 a feed back resistor was open. This resistor and another in series with it supply a sample of the 140 vdc supply and run it into the run regulator on the Diode SIP board.
Proscan PS52682 CTC171 Shut down CTC171. Unit shuts down. Defeated X-ray protect and still shuts down. Gave tech a better way to defeat shut down. Also informed tech about the problem with FB2409 in the Progressive scan circuit which has proven a problem in 5 out of the 6 TVs of this type that are in the shop.
Proscan PS35682 CTC171 Shut down PS35882 CTC170RA Unit runs but will shut down after 2 to 3 minutes. Unit looses the 12 volt run supply. FB2409 was cracked on the chassis near the progressive scan module. Many chassis don't even use this ferrite bead. It is suggested the ferrite bead be jumpered. ONLY FB2409 SHOULD BE JUMPERED!
Proscan PS35682 CTC171 Shut down PS35882 CTC170RA Unit runs but will shut down after 2 to 3 minutes. Unit looses the 12 volt run supply. FB2409 was cracked on the chassis near the progressive scan module
Proscan PS52682 CTC171 Shut down RCA CTC171 Unit will shut off and give the statement "Unit has experienced a power failure" SIP module, C4116, C4117 on the 16 and 7.5 volt supply line were replaced. The statement mean the set got a hard reset. Tech needs to check into the B+ at the output of the SMPS power supply. Power supply was stable but the 12 and 5 volt run supplies kept shutting off. These are switched by the microprocessor and the reset transistors. Q3502 was leaky.
Proscan PS35682 CTC170 Shutdown, Intermittent Intermittent shutdown, also top hooking in picture shortly after turn on. Sometimes blanks out then back on again with the statement stating something about the television has experienced a power interruption. Tech needs to check the condition of CR3604. It is a small glass diode on the signal board next to R3608 the 1 ohm 10 watt resistor. It is recommended to replace it with a 146015 or a 1N4001. This is a plain general purpose silicon diode. There is also a pesky glue on the board that needs to be cleaned off of the area around this diode and board material.
Proscan PS35682 CTC170 Top Hooking CTC170 PS35682. Top hooking in pix. Intermittent no mater what video source is being used. Recommend that tech check out the 2H adjustment on chassis, and determine the correct free running condition. Also inspect the FB2409 in the progressive scan area. FB2409 is known for this type of problem.
Proscan PS35682 CTC170 Top Hooking Top hooking in picture shortly after turn on. Sometimes blanks out then back on again with the statement stating something about the television has experienced a power interruption. Tech needs to check the condition of CR3604. It is a small glass diode on the signal board next to R3608 the 1 ohm 10 watt resistor. It is recommended to replace it with a 146015 or a 1N4001. This is a plain general purpose silicon diode. There is also a pesky glue on the board that needs to be cleaned off of the area around this diode and board material.
Proscan PS52682 CTC171 video PS52682. Unit getting darker and lighter intermittent. Also the picture has a slight instability in the horizontal direction Recommend tech inspect the Ferrite beads FB2409, FB2406, and FB2405. This ferrite beads are very tiny inductors that are known to fracture around the circumference of the device. These devices are to small to handle in field and can be replaced with a small jumper wire made from 32 gauge wire wrap wire.