GE Mark VIe System Manual page 177

8.1.1 I/O Pack Power LED Not Lit
Condition
All other I/O packs on same terminal board have power
lights lit
Some other I/O packs on same terminal board have power
LED lit (or simplex board)
No other I/O packs on same terminal board have power
LEDs lit
Troubleshooting
I/O Pack Power Troubleshooting
Potential Problem
I/O pack power connector
I/O pack failure
I/O pack power connector
I/O pack failure
Terminal board failure
Terminal board power
Terminal board failure
Public Information
GEH-6721_Vol_I_BP System Guide 177