Our organization has recently had 2 Cisco ISR 4331's fail with identical symptoms.
Has anyone else run into a similar issue with this model, and/or do you have any advice on how to proceed?
- Both were in service when they failed unexpectedly. No upgrades or configuration changes were occurring when the failures happened. At the time each failed, one was located in Illinois, the other in Massachusetts. We have 14 ISR 4331's in service.
Symptoms:
- When the router powers on:
- PWR light starts amber and turns to green
- TEMP and FAN lights start amber and then quickly turn green
- STAT light continuously flashes amber the entire time the router is powered on.
- If the router is left on, the PWR, TEMP, and FAN lights will simultaneously flash amber about every 15-30 seconds and then go back to green. The fans change their tone when this happens too, so I suspect the router is power cycling itself.
- If I take out the DDR3 ram sticks and power on the router, the lights go through the same cycle.
The EN console light below the RJ45 port is lit green, but if I plug my PC into the USB port, the USB EN light lights up.
The router appears to be power cycling itself before ROMMON loads, but I cannot find documentation on how to troubleshoot this further. There is no output from the console port or the aux port or the USB console port, and break commands are not working.
I have referred to the following documents. The first led me to conclude the ROMMON is not loading, and the second is not applicable because the ROMMON is not loading.
1. ISR 4000 Power Troubleshooting guide
2. Troubleshoot ISR 4000 Stuck in ROMMON
