3. OPERATION CHECKING ON HARDWARE 
JCY-1900
1950  
DR Service Manual 
 
54 
DOC No. 7ZPNA4409 
 
2)  System status 
The MCB has LEDs that display RCU system status. 
 
The lighting specifications of the LEDs 
LED Name  Lighting Specifications 
“SYS”(Green/Red) 
Lights green when RCU is operating. 
Blinks green when RCU startup. 
Blinks red when RCU shutdown. 
Lights green when RCU is safemode. 
“REC”  (Green/Red) 
Lights Green when RCU is recording. 
Blinks Red when RCU is safemode. 
“ERR”(Red) 
Lights when some error occurs. 
“BATT.OP”(Green/Red) 
Lights Green when RCU is supplied power from the battery 
Lights Red when the voltage of the battery is lower than the rated value. 
“SSD1”  (Green) 
Lights when SSD1 is supplied with power. 
“SSD2”  (Green) 
Lights when SSD2 is supplied with power. 
“FAN”  (Green) 
Lights when Fan is supplied with power. 
“BATT”  (Green) 
Lights green when RCU is supplied with power. 
 
 
 
SYS 
REC
expansion 
ERR
BATT. 
OP 
SSD1
SSD2
FAN BATT.