Siemens 125-3208 Troubleshooting, Power-onInitialization Failure, Unit Fault Condition

Troubleshooting

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	Description
Test Fault
Code/Flashes
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.

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