Merlin 3070 Service And Maintenance Manual page 191

DIAGNOSTIC DISPLAY MESSAGES
The diagnostic display messages are listed alphabetically.
Explanations and actions are included where necessary. Check for
bent or broken backplane pins before replacing any module.
NOTE: In the following steps you may be removing and inserting
modules. The Power Module On/Off switch must be set to Off when
you remove or insert the Power, Feature, or Processor Modules. It is
recommended but not essential that you set the On/Off switch to Off
when removing or inserting other modules.
MESSAGE DETAIL
I / O
*ALL
LSHF
*ALL
16
MEANING
I/O Bus Error
The system input/output bus is not functioning properly.
1.
To verify the existence of the problem, repeat the
sweep (press Next, then Detail).
2.
If the problem persists, remove a Line or Voice
Terminal Module from any slot, check the slot for
bent or broken pins in the backplane, and repeat the
test. If the problem clears, the module you removed
or the pins behind it may be defective. If the
problem persists, repeat this step until all control unit
slots labeled Lines or Intercom are empty.
3.
If the problem persists, check for bent or broken pins
behind the Processor Module. If the pins are
undamaged, replace the module. Repeat
diagnostics.
4. If the problem persists, check the pins behind the
Diagnostics Module. If the pins are undamaged,
replace the Diagnostics Module.
Tone Detector Error
The test apparatus used to check the system's analog
voice network and tone plants is malfunctioning. If this
error persists, the network and tone plants will not be
tested.