TM
9-2320-363-20-1
Table 3-1.
Troubleshooting
(Cont)
Malfunction
Test or Inspection
Corrective Action
8.
PANEL
ELECTRICAL SYSTEM (CONT)
Panel Light Circuits (Cont)
LIGHTS DO NOT
BRIGHTEN.
Disconnect
lead 420B
from electronic dimmer switch. Check for +12 VDC
at lead 420B
with main light switch in bright mode.
.
If +12 VDC is present,
replace
main light switch (page 4-170).
1.
POWER
SOURCE
FOR
24 VDC
RADIO
DOES
NOT
OPERATE.
Step
1.
Check
24 VDC 25A radio
fuse.
.
If defective,
replace 25A fuse
(page 4-204).
Step 2.
Remove
24 VDC 25A radio fuse. Check for +24 VDC
at lead 421W
fuse
connector.
.
If +24 VDC is present, go to step 3. If no voltage is present,
repair lead 421 W to 24 VDC
constant
power bus (page 3-2).
Step 3.
Check
for continuity between ground lead and ground.
.
If continuity is indicated,
go to step 4. If no continuity is
indicated, repair ground lead (page
3-2).
Step 4.
Check
for +24 VDC
at lead 421 R from radio power source connector.
.
If +24 VDC is not present,
repair lead 421R.
Instrument Wiring Circuits
1.
NONE
OF THE
INSTRUMENTS
ON DASHBOARD
OPERATING.
Step
1.
Check
instruments
10A fuse.
.
If defective,
replace
10A fuse
(page 4-204).
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