0025 00
TM 1-6625-724-13&P
0025 00-6
Figure 6. CADU Won't Communicate With the DAU
Is External Power on, green power light on DAU is lit?
NO
Does CADU display
lamp stay on when lamp
button is pressed then
released?
Is 28 Vdc being applied
to DAU?
YES
NO
YES
Is DAU Switch On?
Check that aircraft Aux.
Power Connector has
28 Vdc.
NO
YES
Is CADU to DAU
Cable connected?
NO
YES
Turn on DAU
Replace DAU Fuse
Problem still exist?
Send DAU to
TMDE for repair
NO
YES
Connect Cable
After disconnecting
UTD cable at DAU
does CADU display
lamp stay on?
NO
YES
Replace UTD
Cable
Re-connect
UTD Cable
Replace CADU
to DAU Cable
Does CADU
communicate with DAU?
NO
YES
Replace CADU
Proceed with
normal operation
Replace CADU
Cable
