Step 8 Host Attachment; Step 9 Voltage Checks; Step 10 Verification Test; Step 11 Last Option - IBM 3274 51C Maintenance Information

Step 8 - Host Attachment
If you have reached this step and the IML diagnostics have
not detected a failure, bu t the host CPU site is recording
Timeouts, Control Checks, Data Checks, or Operation
Checks, perform item 1 (Non-Loop Attachment), item 2
(Loop Attaclunent), or item 3 (2400-,4800-, or 9600-bps
Integrated Modem Feature).
1. Host Attaclunent, Non-Loop.
a. Request that the 3274 Online Tests (OLTs) be run.
b. If OLTs indicate a failure or are unavailable, replace
card Nos. 13, 14, and 21. [Removing card No. 21
will destroy the master key (Encrypt/Decrypt). See
paragraph 6.1.3.]
c. Verify card locations and operator panel adjustments
(see Appendix C, paragraph C.2).
d. See paragraph 5.3 (Wrap Test):
2. Host Attachment-Loop.
a. Replace card Nos. 13 and 14.
Note: CPU is recording errors.
b. Verify card and operator panel adjustments (see Fig-
ure ColO).
c. • See paragraph 5.3.4 (Loop Panel Indicators).
• See paragraph 5.3.3 (Loop Wrap Test).
3. Host attachment-2400-, 4800-, and 9600-bps Integrated
Modems.
a. See Chapter 5, paragraph 5.4.5.
b. Go to Entry MAP A130.
Step 9 - Voltage Checks
If you have reached this step and a problem still exists,
measure all voltages. Use Power MAP A120, Step 049,
entry point F. Go to the next step if this step did not
fix your problem or does not apply.
Step 10 - Verification Test
a. Recycle the procedure to verify repair action or to isolate
intermittent and multiple problems.
b. Verify and run IML tests by using the IML pushbutton
and On/Off switch (power on).
Notes:
1. Certain error conditions are defined as nonrecoverable
either by the application program or by the access
method. If the subsystem
will
not go online, call the
PSR or the CE at the host system location.
2. Check the fans for proper operation, and replace if
defective.
Step
11 -
Last Option
a. See the Symptom Repair Ust, Figure 2-12.
b. If the Symptom Repair Ust (Step 11, Figure 2-12)
did not assist you in isolating the problem, use the
following if you want to attempt further problem
determination:
• Appendix B of the Maintenance Concepts manual.
• The
diagn()~tic
test provided by FERS DEMF or a
similar program product to assist in problem
determination.
c. If item b above fails to result in problem isolation and
repair or if you choose not to use item b, request
assistance from the next level of the support structure.
Symptom
Action
1. Any operator panel switch function failure except 1 . • Verify for loose or incorrectly installed cables in the operator panel
power ON/OFF switch (failing indicatiort'can be a assembly. See Figure 0-9.
missing function or a function that is always active).
•
Reseat cable in board location 25,26; or 22 (2400-,4800-,9600-
bps I ntegrated Modem Feature) and verify that cable location is
correct for the 3274 features. Socket 26 is used only for loop
attached machines.
•
Use Figures 0-10 and 0-11 (pages FO-7 and FO-9) to find the card
associated with the switch function failures (reseat/swap card).
•
Verify operator panel cable for continuity. See Figure 0-10.
•
Replace operator panel card.
•
Go to Machine Checkout MAP A 100, Entry Point A.
2. 8421 indicator code is 1101. 2. This code (1101) will appear when an uncustomized system diskette is
used.
3. 8421 indicator code is 0010 and then changes
3. This code will appear when a feature diskette is used.
to 0001 after 60 seconds.
Figure 2-12. Symptom Repair List
Otapter 2. Subsystem Problem Isolation Procedure 2-15