IBM 5280 Manual page 130

H
3
DATA ENTRY MAP
MSR
PAGE 4 OF 14
019
(ENTRY POINT B)
- Probe A-B2B04,
531).
P
OR'
(NIM
Momentarily install a jumper
from A-Cl-TP-040, '- Test POR',
to frame ground (MIM 303).
Up light: On
Down light: Pulses
Are the lights correct?
Y N
020
- Leave probe on A-B2B04,
PORI (l'lIM 531).
Up
Remove the jumper from
A-Cl-TP-040, '- Test POR', to
ground (MIM 303).
light: On
Down light: Off
Are the lights correct?
Y N
021
Power ·off.
With the CE meter set to
the RXl scale,
- Connect the positive lead
to A-B2B04, POR', and
the negative lead to
ground.
Is the meter reading 30 ohms
or above?
Y N
J
K L M
J K L ,.1 MAP 1030-4
022
023
Leave the meter connected
as in the previous step.
Use the net list (MIM
531). Remove each card
in the net, one at a
time, until the meter
reads 30 ohms or above.
Replace the last card
removed.
If all the cards in the
net have been removed and
the meter reading is
still below 30 ohms,
suspect a ground on the
Logic Board.
Defective Diskette/Main MPU
car
d
(A - C 1)
O·1I
M 3
0 3 , 5
0 1 ) •
- If a'Ros Patch' cable
is
connected to the card,
GO TO MAP 0600,
ENTRY POINT A.
024
- Defective Disk/Main MPU Card
(A-Cl) (MIM 303, 501).
- If
a 'Ros Patch' cable
15
connected to the card,
GO TO MAP 0600, ENTRY POINT A.
025
- Probe A-B2B02,
(MIM 531).
'1 MHz Clock'
Up light: On
Down light: On
Are the lights correct?
Y N
ECS397S7
PECS39661
5 5
N P
t-1AP 1030-4