Service and Maintenance 6 
Agilent U1602B/U1604B User’s and Service Guide  129
• If you cannot see a channel
✔ Recall factory default setting by pressing   button on front panel. 
Press F1 to enter Save/Load Setup menu. On page 1/4, press F1 to 
restore the factory default setting.
✔ Check that the scope probe cable is securely connected to the input 
connector.
✔ Check that the scope probe lead wires are securely inserted into the 
connector assembly and that the probe clips are making good contact 
with the probe lead wires.
✔ Check that the circuit under test is powered on, probe clips are 
securely connected to test points in the circuit under test, and ground 
is connected.
✔ Check that the correspond scope channel is being turned on. 
✔ Press Autoscale button to allow the instrument to automatically set up 
all channels.
✔ Contact Agilent Technologies Service Center to obtain technical 
assistance, if necessary.
If you cannot get any response from the instrument, contact the nearest Agilent 
Technologies Service Center to obtain further assistance.