Furuno DD-80 - Manual (Page 91)

B – 5
Self test 2
The test requires an external loop to check I/O. Follow the steps below to carry out the test.
1) Set the DIP switch #4 of S1 to the ON position.
2) Temporarily disconnect input and output connectors J2 and J4.
3) Solder a jumper block between J2 and J4; #3 and #4 of J2 are connected to #1 and #2 of
J4, respectively.
Jumper block consists of XH-6 pin and 4 pin connectors with two short wires as below.
XH, 6 pin XH, 4 pin
#3 - - - #1
#4 - - - #2
4) Change the jumper block between J2 and J5; J2/J6, J2/J7, J2/J8, J2/J9, J3/J4, J3/J5, J3/
J6, J2/J7, J2/J8, J2/J9.
LED status
The LEDs light according to equipment status as follows:
CR2: Lights when receiving NMEA data from J2.
CR3: Lights when sending NMEA data from J3.
CR4: Lights when sending NMEA data from J4 to J9.
CR6: Blinks every second.
CR7: Lights when ROM error is detected, or no signal at J2 for 300 ms.
CR8: Lights when RAM error is detected, or no signal at J3 for 300 ms.
CR9: Lights when SIO error is detected, or NMEA data is input at J2.
CR10: Lights when NMEA data is input at J2.
From left
#2, #3, #4, #6 thru #10
Figure B-3 Location of LEDs