IBM 5280 Manual page 142

B C
I 1
DATA ENTRY MAP
TIME COUNTER
PAGE
2 OF
4
003
- Defective Diskette/Main MPU
card (A-Cl) (MIM 303).
If a 'Ros Patch' cable is
connected to the card,
GO TO MAP 0600, ENTRY POINT A.
004
Power off.
Set the CE meter to the RXI
scale.
Connect the positive lead to
A-BID07, '100 Hz clock', and
the negative lead to Logic
ground.
Is the meter reading 30 ohms or
above?
Y N
005
Leave the meter connected.
- 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
006
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) (
M 1M3 0 3) .
If a 'Ros Patch' cable ;s
connected to the card,
GO TO MAP
0600,
ENTRY POINT A.
A
1
f'1AP
1040-2
007
Probe A-B2B04,
501 ) .
POR'
(MIM
Momentarily install a jumper
from A-CI-TP40, '- Test POR',
to Logic ground (MIM 303).
Up light: On
Down light: Pulses
Are the lights correct?
Y N
003
- Leave the probe connected.
- Remove the jumper installed
in the last step.
Up light: On
Down light: Off
Are the lights correct?
Y N
II
~O:ower
off.
- Set the CE meter to the RXI
scale.
- Connect the positive lead
to A-B2B04, POR', and
the negative lead to Logic
ground.
Is the meter reading 30 ohms
or above?
Y N
3 3 3 3
D E F G
ECS40S74 PECS397S7
MAP 1040-2