Slave SEM02 died - Any way to diagnose?

[srooks]

My comfort system is reporting communications failure (33) - having alarmed with tamper alert.
On investigation, I see in the log RS485 Communication failure - which is to the slave.
Looking at the SEM02 board, neither of the LEDs (Red, Green) are lit,however the power supply seems fine and I\'ve checked the voltage.
Is there any diagnosis I can perform on the SEM02 to identify what\'s gone wrong?!

Cheers,

steve

[slychiu]

If the red and green leds are off on the SEM it means that there is no power supply or the procesor is faulty. Do a Reset on the SEM02

How is the power supplied to the SEM02? Is it by the 4 way RS485 cable? Perhaps the cable has a fault Try using the 12V /GND connector

[srooks]

Power is supplied via the 12v/0v connector (not RS485). I\'ve checked this connection using a multimeter and it\'s at 13.8v.
Reset does nothing. Other boards have power.

I\'m running a Comfort I (SEM is 8 yrs old, First 4.164). Can I replace the SEM with a new one, or will there be firmware issues?

[slychiu]

Check out the Slave compatibilty document which shows which Comfort I/II firmware is compatible with Slave Firmware