Loewe Concept L 42 Platinum, Loewe Concept L 42 Anthracite – Plasma TV – faults, reset, software update, Service mode and other adjustments

If a repair exchange has to be carried out, special care has to be taken of the so called E/X Tube. Via this sealed glass tube the panel is bleeded first, after that it becomes filled with gas. If this tube becomes broken, the panel is totally lost. Also when changing the panel, take care of the flex cables, any damages will also lead to a total loss of the panel, as those cables are bonded between the glass layers of the panel.
On the so called Type Labels you will find the panel type and the serial number of the panel. This information should be noted on the delivery notes in case of repair exchange.
Schematic Configuration
The schematic configuration of the panel shows, which PCBs belong together and which signals are conducted to the panel. The mentioned voltages Vs, Va and Vcc are from the PSU, which is part of the panel. Any exchange of the PSU by untrained persons is not recommended, as the voltages on the PSU have to be adapted to the corresponding panel.

General Reset In the service menu (open with ”8640”, ) under the sub-menu ”reset all” a complete reset can be done. CAUTION: Here the operating hours as well as the channel storage will be erased.

Over temperature - switch off
”WARNING” will appear, as soon as the temperature on the AV3 electronics exceeds 60DegC (Temperature 1)..
The unit will be switched to Stand By, the red LED is lit as soon as the temperature on the AV3 electronics exceeds 65DegC (Temperature 2)

It is possible to switch on the unit again via remote control.

The unit will be switched to Stand By, the red LED starts to blink as soon as the temperature on the AV3 electronics exceeds 70DegC (Temperature 3). It is not possible to switch on the unit again via remote control.  As soon as the temperature is below 60DegC, the LED stops blinking, it is possible to switch on the unit again.

Software Update

You need:

Update Program ”FlashUpgrader.exe” (for Windows 98 and Windows ME) or ”FlashUpgraderNT.exe” (for Windows NT4.0, Windows 2000 as well as Windows XP). Under Windows 95 the update is not possible.

Actual software (the update software as well as the actual software release for your device is available as zip file at your LOEWE service

Null Modem cable (serial date cable (RS232) with 9 pin female connector on both sides, the wires must be crossed)

Update:

Unpack Update Program and new Software into a new directory.

Switch off unit (mains switch).

Start Update-Program.

Select via”Choose...” file ” *.inf” in the new directory with the firmware data.

Set ”Connection” to ”serial”, select the used Com port as well as the Baud—rate (recommended 115200).

All other options remain on ”default” position.

Click on “Flash” anklicken, the program is set to stand by.

Switch on the device using the mains switch. The program starts automatically; the progress is shown on the display. Depending on the selected Baud—rate, the update takes about 3to6 minutes.

Typical Faults

In the case of malfunction, it is recommended to check the external wiring before opening the unit:

Mains power available?

Are the corresponding signal cables connected?

Is there a signal available from the external sources?

Is the corresponding signal source selected?

Also after opening the unit it is recommended to check the internal wiring and connectors to exclude any loose contact.

No display (on all signal modes)

Check In /Outputs of power supply. 

Not possible to switch unit on (remains in Standby)

Check IR remote control (batteries!)

Reinstall software 

Check AV3-electronic 

Missing lines or columns

Check display 

Pixel faults

Due to technological reasons single pixels or sub pixels might fail on TFTs as well as on Plasma displays. 

As long as the number of faults is within the limits mentioned in the specification, there is no device defect exists.

Missing colors
Check data cable
Check AV3
Check display
Channel search not working / not working properly
Check AV3

Flat-display connectors
If there should be a repair or just a check on a LCD or Plasma panel, it will become necessary to disconnect some of the connectors. Sometimes this is quite complicated, disconnection only with force will lead to total defect of the panel in the worst case. Below there are the most common connectors and how to disconnect them:

Fault finding [Without opening the unit]
Analysis Front LEDs
Red LED remains lit in spite of switching unit on with remote: device stays in standby, possible faults are IR remote control or AV3..
Green LED but no picture: device is active but shows no image, possible faults are: wrong input source selected or panel defective.
Red and green LED is lit at the same time: unit is in an undefined state, fault caused mostly by AV3
Analysis Screen
If with a black screen (no image is displayed) a light gleam is still visible (darken point of view with hand), normally the problem is located in the signal routing and not on the panel itself.
Acoustic Analysis
When switching between the different input sources, there is a gentle click of a relies to be heard. If this is not audible, the problem is certainly located on the AV3.

With open unit
Check supply voltages (use the pins of the connectors for testing points
Problem containment (by means of checking and / or exchange of single PCB’s)..
Noisy picture in tuner mode
Signal level must be higher than 68dbV (typical level of cable TV)
High noise level on RF signal (poor SNR)
Adjust DNC to max. (OSD)
Due to the digital signal processing flat panels are more sensitive to noise levels than 50Hz interlace CRTs or 50Hz progressive CRTs (8Bit resolution, False Contouring, Dithering, De-interlacing, limits of the used PDPs, ...)
Noisy picture in Video mode
High noise level on Video signal (poor source)
Adjust DNC to max. (OSD)

Due to the digital signal processing flat panels are more sensitive to noise levels than 50Hz interlace CRTs or 50Hz progressive CRTs (8Bit resolution, False Contouring, Dithering, De-interlacing, limits of the used PDPs, ...).  If possible do not use FBAS signals, better is SCART-RGB or S-Video.

Regular horizontal or vertical stripes in Video picture

Change position of external signal wiring (emission of PDPs)

Humming loop (ground shift)

Video picture only in black and white

Poor signal level or non-standard signal

Signal not supported (e.g. NTSC via RF)
At channel search, not all channels are recognized or recognized with the wrong name.

Device is not supporting PDC

Device is working with internal channel name table, if the channel name changes shortly, this may lead to wrong information

Image is flat and low contrast (Video/VGA)

The factory defaults for brightness and contrast are suitable for most applications, only for exceptions this settings should be changed

Also other settings and adjustments might influence the picture quality, for this reason always first reset to factory defaults (OSD Menu).

Picture out of focus in VGA-Mode
Max. Resolution of 848x480 is recommended
In rare cases (poor signal quality or unfavorable display), auto—adjustment is not able to work correctly (see the Operating manual), select manual adjustment in the OSD
Adjust focus in menu Picture to the signal source.

Startup sequence AV3 in connection with the PSU of the Plasma:

1. On CN801 of the PDP PSU, Pin3, +5VDC appears.

2. CN801, Pin1 (ACDET) switches to ”high”, as soon as the voltage from the PSU becomes higher than 90VAC. If the voltage remains under 90VAC, the startup will stop here (is interrupted by the AV3).

3. To start the plasma, the signal RYLON (CN801, Pin2) is set to 5V, which causes the startup of the low voltages on the PSU, as e.g. 5V, 12V, 30V, etc.

4. The signal 5VDET (CN801, Pin6) is under surveillance. If the signal is ”low”, the AV3 will set RYLON = 0V (this causes the switch off of the panel).

5. On ”high”- signal (RYLON = 5V) the AV3 will set VSON to ”high” (CN801, Pin5) and will switch also the high voltages, the panel is under operation.

Service OSD
Beside the User-OSD there is an additional Service-OSD, in which settings and adjustments can be made which will change the performance of the display, alternatively will show information which are helpful for service. For this reason the access to this menu should only be done by any experienced service technicians.
To enter the service menu, first the user menu has to be opened (button ”menu” on your remote control), afterwards you can enter the service menu by typing the code ”8640” on your remote control.
The service menu will appear (the values which are shown are only wildcards and will differ in most cases from the effective values).

Version / System Info
Sub menu Version / System Info shows the actual software version, the hardware version and the audio processor type (MSP).
There are no adjustments possible. In all service cases, where consultation with the manufacturer should be necessary, for this information will be asked.

Operation Time
Sub menu Operation Time shows the operation time of the complete unit (also standby) as well as the operation time of the panel.
Via”Reset” both values can be reset to ”0” . This is necessary when, e.g. the panel has been exchanged during repair.
CAUTION: If here the values are reset to ”0”, there is no other possibility to assess the operating time of the device. It is highly recommended to record the operating time in written form in the repair form or in different form.

Default Color setting
In sub menu Default Color Setting the basic adjustment of the colors for all input sources is set.
The offset value defines the color temperature for the complete display, including the background; the gain-value influences the colors of the image content.
As a basic principle it should always be tried to do any color adjustments via the user menu, for certain applications, however, it might be necessary to do adjustments in this menu (e.g. applications in T.V. producing branches).

Temperature Setting
The AV3-electronics contains an implemented temperature-control, which consists of three steps

The factory made values are for optimum operation of the device and should only be changed in extreme individual cases after consulting the manufacturer.
Any defects, caused by unauthorized changes in the temperature control, will automatically lead to loss of any warranty claims.
For service purpose it is possible to reset the Max.— / and MIN.—Temperature. This allows checking, if the unit moves towards critical temperatures at certain applications.

Sub Volume
Sub-menu Sub Volume sets the pre-adjustment for the volume of all input sources, respectively Line out Audio.
Factory-made all levels are set to the same value, in some cases the output levels of some peripheral devices on customer side might be different. For this, the customization can be done here.

Reset Everything
With Reset Everything all adjustments, the channel memory, the Max.— / Min.—Temperatures as well as the Operating hours will be reset, which means the device is in the same status as originally delivered by the manufacturer.  This should only be done after consulting the manufacturer, as with the erased temperatures and operating hours important information will be lost which might be necessary for warranty claims.

Life Expectancy

The anticipated life-time is estimated about 60.000 hours of continuous operation. Average life-time is the time when the brightness level becomes half of its initial value.

Typical Faults

Following examples are typical panel faults. It is assumed that whenever a row or column is missing completely or partly, the problem is caused by a problem in the plasma electronics and not by external electronics

Power Supply Unit (PSU)

To discover any problems of the plasma panel, it is most simple to check the voltages on the PSU. Consider that not all voltages are present in case of failure, as the PSU is dependent of a handshake voltage from the panel

LVDS-Interface-Board

The LVTTL signal, which is present at the output of the AV3 electronics, is generated into a LVDS signal, which is necessary for operating the plasma, on the LVDS-Interface-Board (LVDS= Low Voltage Differential Signal).  The board is mounted fix to the AV3 via connector X2, the changed signal (LVTTL to LVDS) is routed from X1 directly to the logic board of the plasma. The supply of the LVDS-Transmitter IC is also solved via X2 (Pin 15 -18 = +5V; Pin 1, 2, 19, 20, 29, 30, 39, 40, 49, 50 = GND)