Siemens TC12 Installation, Commissioning And Maintenance Handbook page 61

2.4.6.2 PC Failure
Symptom
PC not Powered
SIP PC 1 LED ON
Note. If it becomes necessary to replace an IMD distribution box or the
associated PCB they must be replaced in pairs.
2.4.6.3 Modem Communication Problems
Symptom
No communication from one
modem on modem PCB -
others OK
No communication from all
four modems on Modem
PCB
No communication from all
modems in one rack
2.4.6.4 Digital Output PCB Problems
Symptom
Power LED not on
Watchdog Fail LED ON for
all PCBs connected
666/HE/43100/000
TC12 Installation, Commissioning & Maintenance Handbook
Possible Reason
PC Switched off.
Power cable disconnected/faulty.
Mains plug fuse blown
Master switch panel off/fuse blown.
PC faulty.
Digi I/O card card/cables installed incorrectly.
Digi I/O card faulty.
PC Not running TC12 software. Check software
installation and re-boot PC.
Software has failed - ignore all other SIP LEDs/audio
(software driven). Re-boot PC. Re-install software
and re-boot.
Possible Reason
D-type disconnected from IMD distribution module
Modem/IMD cable faulty
Incorrect MDF connection
OTU Disconnected/faulty
Incorrect Mode set on Modem PCB.
Radial system with modem PCB to transformer PCB
cable, disconnected/ faulty
Modem/IMD cable not connected/ connected to
wrong four D-types/ cable faulty
No power to modem PCB - check power LEDs,
check modem PCB to PSU PCB cable
Telephone line connection problem at MDF
No mains connection to PSU PCB
Low Voltage side of PSU not connected on PSU PCB
PSU faulty on PSU PCB
No PSU PCB to modem PCB cables attached
IMD card/cables installed incorrectly/ faulty
Possible Reason
PSU PCB to Digital Output PCB ribbon cable not
connected or faulty.
Problems with PSU PCB i.e. fuse blown/no power to
PSU/faulty PSU
Check SIP Panel PC 1 LED. If on, PC software is not
running - reboot PC
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