Juniper Networks M160 manual Blown Fuse Indicators, Fuse Locations in the Fuse Box

Troubleshooting Hardware Components

LCD Message	CLI Message
interface-name so- x / x / x SEF	interface-nameso- x / x / x - SONET severely errored
	frame
interface-name so- x / x / x UNEQ	interface-nameso- x / x / x - SONET unequipped

Blown Fuse Indicators

The router uses fuses from the Cooper Bussman brand GMT series for the FPCs, MCSs, PCGs, and SFMs. They are located in a fuse box on the rear of the midplane. When the fuse for a component blows, the component stops functioning even though it is installed correctly and the power supplies are still providing power to the router.

Figure 107 shows the location in the fuse box of the fuse for each component. The labels shown in the figure do not appear on the actual fuses (the clear cover on every fuse reads BUSS GMT-X), but a table on the surface of the midplane below the fuse box displays the same information.

Figure 107: Fuse Locations in the Fuse Box

J243	J242	J244	J241
A B C D A B C D A B C D A B C D
MCS0 12A SFM0 10A FPC7 15A FPC6 15A	FPC5 15A SFM1 10A MCS1 12A SFM3 10A	SPARE 1A SPARE 10A SPARE 12A SPARE 15A	SFM2 10A FPC4 15A PCG1 1A FPC3 15A

J240

FPC2 15A A

FPC1 15A B

FPC0 15A C

PCG0 1A D

1238

When a fuse has blown but the power supplies are still delivering power to router, the amber LED adjacent to the fuse lights. For vertically oriented fuses (in the groups labeled J241 through J244 in Figure 107), the LED is located below the fuse; for horizontally oriented fuses (in the group labeled J240), it is to the left of the fuse.

NOTE: The LEDs are each about 0.1” (2 mm) square. They might be difficult to see when not lit.

Another indication that a fuse has blown is that the colored indicator bulb inside it becomes visible through the clear cover on the fuse. For information about the indicator bulb color for each fuse type, see Table 25.

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