Service manual

Specifications
ComPair consists of a Windows based faultfinding program and an interface box
between PC and the (defective) product. The ComPair interface box is connected to the
PC via a serial or RS232 cable. In case of the EM1.1U chassis, the ComPair interface
box and the TV communicate via a bi-directional service cable via the service connector
at the rear side of the set (located at the left side of the rear cinch connectors, see also
figure 1-2).
The ComPair faultfinding program is able to determine the problem of the defective
television. ComPair can gather diagnostic information in two ways:
• Automatic (by communication with the television):
ComPair can automatically read out the contents of the entire error buffer.
Diagnosis is done on I
2
C level. ComPair can access the I
2
C bus of the
television. ComPair can send and receive I
2
C commands to the micro controller
of the television. In this way, it is possible for ComPair to communicate (read and
write) to devices on the I
2
C busses of the TV-set.
• Manually (by asking questions to you):
Automatic diagnosis is only possible if the micro controller of the television is
working correctly and only to a certain extend. When this is not the case,
ComPair will guide you through the faultfinding tree by asking you questions (e.g.
Does the screen give a picture? Click on the correct answer: YES/NO) and
showing you examples (e.g. Measure test-point I7 and click on the correct
waveform you see on the oscilloscope). You can answer by clicking on a link
(e.g. text or a waveform picture) that will bring you to the next step in the
faultfinding process.