Troubleshooting/Service 
326  UDC3500 Universal Digital Controller Product Manual  3/07 
 
7.7.7 Procedure #7 – Keyboard 
Table 7-11 explains how to troubleshoot a Keyboard failure. 
Table 7-11  Troubleshooting a Keyboard Failure 
Step  What to do  How to do it 
1 
Make sure the keyboard is 
connected properly to the 
MCU/output and power/input 
boards. 
Withdraw the chassis from the 
case and visually inspect the 
connection. 
2 
Controller Keyboard or specific 
keys may be LOCKED OUT via 
the security code. 
Use your four-digit security code 
number to change the lockout 
level. Refer to Section 3 – 
Configuration. 
3 
Run the keyboard test.  Simultaneously press both the 
 
Func
Loo
 1/2
 key and the 
SetupSetup
key. 
 
The controller will now run a 
display test that lights every 
element in the display. Following 
that test, you will then see: 
 
 
TRY ALL
Lower Display
KEYS
Upper Display
 
Press each key. If instrument 
reads the key, then the key’s 
name will appear in the lower 
display. After fifteen seconds, the 
unit returns to normal operation. 
4 
Replace the Display/Keyboard 
Assembly if any keys do not 
function. 
Refer to “Parts Replacement 
Procedures” in this section.