Tait TM8000 Series, Руководство по обслуживанию

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160 Servicing of Control Head TM8100 Mobile Radio Service Manual
May 2004 © Tait Electronics Limited
Task 5 —
All Keys Faulty
If all the keys, with the exception of the
ON
/
OFF
key, are faulty, repair the
control head as follows:
1. Disconnect the control-head loom. Replace IC4 [at 1C2], which
reads the status of the keys. See
Figure 7.2 .
2. Reconnect the control-head loom and test the keys to confirm the
removal of the fault. If the fault has been removed, return to
Subsection 5.2 (on page 109) . If it has not, replace the control-
head board as described in Subsection 7.4 (on page 163) .
7.3 Replacement of Faulty Component
Introduction
This subsection gives the procedure for obtaining the correct
replacement for any faulty component on the control-head board. There
are four steps:
■
identify version of PCB information pack applicable to board
■
identify replacement component in BOM of PCB information pack
■
consult technical notes
■
obtain replacement component
The technical notes will indicate whether there have been any changes
affecting the component in question.
Identify PCB
Information Pack
First identify which version of PCB information pack applies to the
control-head board under repair:
1. Note the IPN of the PCB. The IPN is printed at one corner of
the board as shown in
Figure 7.1 to Figure 7.3 . The last two digits
in the IPN comprise the issue number of the PCB.
2. Compare the issue number in the IPN with that in the PCB
information pack supplied with the service documentation.
3. If the issue numbers match, consult the BOM as described in the
paragraph following the next. If the issue number indicates that
the board is either an earlier or a later version, continue with
Step 4.
4. Obtain the PCB information pack for the board under repair. If
a copy is not available, refer to the Technical Support website as
described in the next paragraph.