IBM 5280 Manual page 266

B
3
COMMUNICATIONS MAP
EIA WRAP ERROR MAP
PAGE 4 OF 12
004
- Remove the wrap connector.
Note: The 'Received'
displayed may change with
line
the
wrap connector removed. Ignore
this byte for now.
- Probe the 'Transmitted' line at
probe point
F.
Up light: On or Pulsing.
Down light: On or Pulsing.
Are the lights correct?
Y N
005
THE SYMPTOMS INDICATE THAT THE
'TRANSMITTED' LINE IS LOSING THE
SIGNAL.
Probe the 'Transmitted' line
at probe point D.
Up light: On or Pulsing.
Down light: On or Pulsing.
Are the lights correct?
Y N
006
Probe the 'Transmitted' line
at probe point C.
Up light: On or Pulsing-
Down light: On or Pulsing_
Are the lights correct?
Y N
655
C D E F
F MAP 3019-4
007
Probe the 'Transmitted' line at
probe point B.
Up light: On or Pulsing-
Down light: On or Pulsing.
Are the lights correct?
Y N
008
Probe the 'Transmitted'
at probe point A.
line
Up light: On or Pulsing_
Down light: On or Pulsing_
Are the lights correct?
Y N
009
Power off.
Remove the communications
MPU card.
Use the CE meter on the RXl
scale to measure the
resistance to a ground pin.
A short will read less than
20 ohms. Measure the
'Transmitted' line at probe
point A.
Is the line grounded?
Y N
555
G H
J
010
Defective communications
MPU card <A-ES)(MIM 811).
If a 'Ros Patch' cable is
connected to the card
p
GO TO MAP 0600
p
ENTRY POINT A_
EC840874 PEC839787
MAP 3019-4