Keyboard Cable Check Mini Map; Conditions After Power On; Service Aids; Tools - IBM 5251 11 Maintenance Information Manual

140
I
KEYBOARD CABLE CHECK MINI MAP
• Use this figure to locate an open in the cable check
• For Mini MAP example, see Troubleshooting Aids (212).
Conditions after Power-on
• Both the '-cable check A' and '-cable check B' lines
are at a Down level.
Service Aids
• The d,isplay' station will
not
be damaged if
powered-on after the keyboard cable is
disconnected.
Tools
Connect the CE probe as follows:
• +lead-1-G-D03
• -lead-1-G-D08
• Ground-1-B-D08
I
I nterposer I
I
I
I I
Planar
Board
Internal
Keyboard
Cable
I
I
I
13
I
Keyboard
Signal
Cable
I
Connector B
I
-!-I~tt
-1-"
-r
~7J~~C=1.~
1 25
I
14
I .
I
I
I
I
B02 D02
I
B02
I
I
I I I
I I
I
I
-Cable Check A
I
1-B-B02
I
Access
Panel
1
I «
»
»
I
I
21
B02
B02
~
I
I
D12
1-30
Keyboard Logic
Printed Circuit
Board
-I
j
1-8-012
!
K~----~~~~----------------~'~--------------~>-----~
»
~
-Cable Check B
I I
I I