Symptom Explanation Conditions That Could Cause This Symptom A status code or a symptom is
•
Defective driver/receiver card in location .10.indicating a host-to-3174
•
Defective channel adapter card in location 11.communication problem.
•
High/Low Priority switch not set to High or Low.•
Improper customizing option or attachment response number.•
Host unit control word (UCW) assignment for 3174 is improper.•
Bus and Tag cable block pins or socket pins are bent or broken.CAUTION:
To avoid the possibility of electrical shock, switch off power and disconnect power cord before
disconnecting cables or removing a component, such as the planar board, power supply, or diskette drive.
(For translations of this safety notice, see Safety Notice 10 in IBM 3174 Safety Notices, GA27-3824.) Warning: Before switching power off, go offline and then set the Power Control switch to the Local position.
~
- Perform an Alt 2 IML. See "Alt 2 IML Procedures (Test 82)" on page 1-56.
Is 2082 displayed?
Yes No
110021
Use the status code to find the repair action in the 3174 Status Codes manual.
Check for any status code(s) in the event log pertaining to the channel adapter (HG16) in At a 3278 or similar display, run the test 1 event log (option 2). See "Test 1: Display Logs Menu" on page 2-169.
Scan the following chart sequentially and match your problem to a symptom in the chart then go to the action for that symptom.
SYMPTOM ACTION
Host system is indicating a message of channel overrun or Check the High/Low Priority switch setting. See
lost data. "Priority Switches" on page 4-2.
Host or 3174 problem after successful customizing or Go to Step 004.
installation.
Problem after 3174 had been working. Go to Step 006 on page 2-75.
1004
1
(From step 003)
- Check that the High/Low Priority switch is set to the High or Low position. See "Priority Switches" on page 4-2.
(Step 004 continues)
2-74
3174 Models 1L, 1R, 2R, 3R, 11L, 11R, 12R, and 13R Maintenance Informationpage 2-175.
Verify that the proper unit control word (UCW) subchannel assignment for the 3174 has been made in the host. (Consult with the host service representative if necessary.) The 3174 will operate with shared or unshared UCWs and will support disconnect command chaining (DCC). (Block multiplexer channels on some host systems do not support DCC with shared UCWs.) For non-SNA attachment a shared UCW with disconnect command chaining is recommended. For SNA attachment, an unshared UCW is recommended. Several factors, such as other controllers on the channel, availability of UCWs, and priority, should be considered when assigning UCWs. Sometimes a deviation from the above
recommendations will degrade system performance. For more information about UCWs, see Chapter 4.
Does the channel to the 3174 still fail?
Yes No
110051
Return the 3174 to operational status with a normal IML from the Control diskette or from the fixed disk. See "Normal Initial Microcode Load (IML)" on page 1-53.
(From steps 003 and 018)
- Check that the High/Low Priority switches are set to the High or Low position. See "Priority Switches"
on page 4-2.
Do you have spare cards for locations 1 0 and 11?
Yes No
110071
Go to Step 017 on page 2-76.
Before removing the channel cards, perform the channel card Warning procedure before replacing the following cards. See "How to Remove the Channel Adapter or Channel Driver/Receiver Card" on page 2-288.
Replace the driver/receiver card in location 10.
Replace the channel adapter card in location 11.
Use the channel Warning procedure again to restore the 3174.
Perform an Alt 2 IML. See "Alt 2 IML Procedures (Test 82)" on page 1-56.
Is 2082 displayed?
Yes No
110091
Use the status code to find the repair action in the 3174 Status Codes manual.
Perform a normallML (see "Normal Initial Microcode Load (IML)" on page 1-53). to load the
operational code and then go online to verify the repair. See "How to Place the 3174 Online (Models 1 L and 11 L 'Only)" on page 2-287.
(Step 010 continues)
MAP 0920 (continued)
010 (continued)
Does the channel to the 3174 still fail?
Yes No
~
Return the 3174 to the customer.To run the driver/receiver wrap test, you will need the following items.
Wrap plug
- Run OLTs if available in your host system configuration. See the OLTs in Chapter 2 under "3174 Display Subsystem OL Ts."
If the problem still exists, use your support structure for aid.
(From step 019)
- Perform the driver/receiver wrap test. See "How to Run the Channel Driver/Receiver Wrap Test (FN 01)" on page 2-140.
Is 2016 displayed?
Yes No
~
- Verify that the Priority switches are set to either High or Low priority.The wrap test results will show a failing code of 3011 and the associated 'bus in' and 'tag in' signal line(s) that are failing. Inspect the signal line(s) relating to a Bus In or Tag In socket pin(s) for a possible defect. See the "Wrap Test Analysis" on page 2-142.
Replace the driver/receiver card in location 10.
Replace the channel adapter card in location 11.
Replace the I/O board (bus/tag tailgate assembly) only if you are absolutely sure the cards are not defective and the wrap test procedure was properly followed. See "How to Run the Channel Driver/Receiver Wrap Test (FN 01)" on page 2-140.
The path to the Tag Out and Bus Out sockets are not tested with the wrap test. Visually inspect the Tag Out and Bus Out sockets for bent or broken pins.
Run OLTs if available in your host system configuration. See the OLTs in Chapter 2 under "3174 Display Subsystem OL Ts."
If the problem still exists, use your support structure for aid.
§]
(From step 007) (Step 017 continues)
2-76
3174 Models 1L, 1R, 2R, 3R, 11L, 11R, 12R, and 13R Maintenance InformationWrap plug Wrap plug Terminator Terminator
PIN 56X4829 PIN 6246339 PIN 2282676 PIN 2282675 Do you have the wrap and terminator plugs?
Yes No
~
- Run OL Ts if available in your host system configuration. See the OL Ts tests in Chapter 2 under"3174 Display Subsystem OLTs".
Obtain the cards for location 10, 11 or the wrap plugs to isolate the problem. Go to Step 006 on page 2-75.
Go to Step 014 on page 2-76.