Agilent Technologies 8935 Series, Manual

Page: 54 / 343

Chapter 3 53
Troubleshooting
Self-Test Diagnostics (Step 1)
Figure 3-4 Power Supply LEDs
3. Check the LEDs on the A2A31 Controller assembly, see Figure 3-5
on page 53 . The LEDs should all light up immediately on power-up,
and then go off several seconds after a beep is heard. If the LEDs do
not light when the Test Set is powered-up, either the Controller or
the Memory/SBRC (A2A30) assembly is faulty.
Figure 3-5 A2A31 Controller Assembly
4. If the Test Set does not power-up properly, but the fan operates and
the power supply voltages are correct on the Power Supply Regulator
(A3A1) outputs, the Controller (A2A31) may be failing. Check TP2 on
the Controller for +5V. If +5V is present, the Controller assembly is
faulty.
5. If there is no display, but VIDEO OUT port on the side-panel has the
signal shown in Figure 3-6 , then the A1A1 Display assembly is
faulty. If the signal is not present, then Display Drive A2A50
assembly is faulty.
0
k1
k1©
k2
k3
k4
Shift
k2©
k3©
k4©
Me
nu
Pau
se/
Con
tin
ue
CD
MA
Ge n
RF
G
CD
MA
Anl
Res
et
R
LEDs
1
2
3