Wednesday 19 August 2020

REPAIRING / SERVICING TV ROLSEN RL-19L1005U

Technical description and composition of the ROLSEN RL-19L1005U TV, panel type and modules used. The composition of the modules.
ROLSEN LED
Model: RL-19L1005U
Chassis / Version: MST6M182VG-LE2
Panel: 19 inch
LED driver (backlight): integrated into PSU
PWM LED driver: BIT3251
MOSFET LED driver: BA1S1F
Power Supply (PSU): MP113-L18
PWM Power: PWM SOT23-6
MainBoard: AS MST6M182VG-LE2
Tuner: ET-6N1E-CF101R
RL-19L1005U Specifications
ROLSEN RL-19L1005U
General recommendations for TV LCD LED repair
Repair of the ROLSEN RL-19L1005U TV should begin with a fault diagnosis, which involves a careful examination of the external and internal elements of the device. Specific external damage to some elements can sometimes indicate further actions to determine the malfunction of the TV and localize the defect before starting the necessary measurements. In some cases, defective elements are visible with the naked eye, for example, charred resistors or swollen sintered capacitors, or electrolytic ones in rectifier filters. The formed ring cracks in the soldering of the terminals of transformers or heating circuit elements are also frequent sources of many malfunctions with a variety of external manifestations.
If the MP113-L18 power supply module fails, external manifestations may be different, for example, the ROLSEN RL-19L1005U does not turn on at all and there is no indication of the control lamps on the front panel. With the same symptoms, the regulator (converter) of the control processor power supply may be faulty. When diagnosing and repairing the power supply, first of all, replace the swollen capacitors of the secondary rectifier filter and check the fuse and, if it is broken, the cause must be identified. Often in such cases an avalanche (thermal) breakdown is detected in the power semiconductor elements of the module - rectifier diodes and transistors in the primary circuit.
Power switches in switching power supplies (SMPS) fail for no reason very rarely and, in case of their breakdown, it is necessary to look for a malfunction in the stabilization circuits, checking electrolytic capacitors, semiconductor devices and resistors in the primary circuit. The reason may be a malfunction of the PWM regulator microcircuit, which can only be checked by replacing it with a new or known good one.
In cases where the ROLSEN RL-19L1005U TV has lost the image, but there is sound and all other functions are operational, there is a possibility of a malfunction of the LED driver (the converter for powering the panel backlight LEDs). When you turn on the TV, the image may appear briefly and immediately disappear. It should be borne in mind that with such manifestations, the LEDs themselves fail.
Often, in the absence of backlighting, disassembly of the panel is required. It is necessary to check the serviceability of the LED transitions, as well as the reliability of the contact connections in the lines and connectors.
It should be remembered that it is not possible to determine an open circuit in the LED lines without disassembling the panels using a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required.
Repair or diagnostics of the AS MST6M182VG-LE2 motherboard should begin with checking the stabilizers or power converters of its microcircuits. If necessary, you should update the software (software).
A malfunction of the tuner ET-6N1E-CF101R is established after checking the software and all supply voltages at its terminals, including the supply voltage of varicaps (30-33V).
We remind users again! Attempts to repair the ROLSEN RL-19L1005U TV without proper qualifications and experience can lead to its complete non-repairability!

DOWNLOAD SCHEMATIC DIAGRAM  / SERVICE MANUAL psu  ------------------>    MP-113-Y18





 The main features of the ROLSEN RL-19L1005U device:
Installed matrix (LED-panel) 19 inches.
To power the backlight LEDs, a converter combined with a power supply is used, controlled by a BIT3251 PWM controller. The keys of the BA1S1F type are used as power elements of the LED driver.
The formation of the necessary supply voltages for all nodes of the ROLSEN RL-19L1005U TV is carried out by the MP113-L18 power module, or its analogs using PWM SOT23-6 microcircuits.
MainBoard - The main board (motherboard) is an AS module.
Tuner ET-6N1E-CF101R provides reception of television programs and tuning to channels.
ROLSEN RL-19L1005U LCD TV, diagonal 19 "(48 cm) in 16: 9 format. Necessary screen brightness of 300 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 100,000: 1 is achieved by special control of LED operation. -Panels of this TV are equipped with edge lighting from LEDs - Edge LED.It is possible to view images in high quality HD at a resolution of 1366x768 pixels in the standard graphic resolution 720p (HD Ready) .Input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal shaping takes place in the standards 480i, 480p, 576i, 576p, 720p, 1080i Supported multimedia file formats: MP3, WMA, MPEG4, MKV, JPEG.
Speaker power of 6 W (2x3 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, SCART, VGA, HDMI, USB. A headphone output is provided. To connect a computer or laptop to this TV model, use the VGA (D-Sub 15) connector on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768.
The power consumed by the TV in operating mode from the network is 40 watts.
TV weight: 3.6 kg.
Attention! The panel of the ROLSEN RL-19L1005U LED TV is an expensive and unreliable element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.