Siemens SED2 VFD Electronic Bypass Option 125-3208 - Manual (Page 59)

Troubleshooting
Siemens Building Technologies, Inc. 51
Troubleshooting
WARNING:
Always disconnect all power sources before opening the SED2 Electronic
Bypass Option.
Power-on Initialization Failure
(Unit Fault Condition)
During power-on initialization, a unit fault condition occurs if the Electronic Bypass
Option did not pass the basic sanity test. Rather than flash normally, the basic sanity
test indicator pauses, flashes a fault code, and then repeats.
Table 7 shows the fault codes. For example, if the basic sanity test indicator flashes
three times rapidly, pauses, and then repeats, this means that there is a keypad
failure.
Table 7. Basic Sanity Test Fault Codes.
Basic Sanity
Test Fault
Code/Flashes
Description
1 Non-Volatile Memory Failure
2 Flash Memory Failure (CRC, cyclic redundancy check)
3 Keypad Failure
4 RAM Memory Failure (not used)
5 EEPROM Read error
6 EEPROM Write Failure
7 Runtime Flash Failure (CRC, cyclic redundancy check)
8 Main Program Failed (or hangs)
It may be possible to recover from the unit fault condition by simply attempting a
power down/up of the Electronic Bypass Option. If the unit fault condition still exists,
replace the Controller board.
CAUTION:
When powering down/up the Electronic Bypass Option, power down the unit,
wait 5 minutes, and then power up the unit.