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Fault Detection and Troubleclearing
Release F UMC800 Controller Installation and User Guide 89
4/01
Modem troubleshooting
Controller modem problems will typically show one of two symptoms.
• The modem does not answer, or
• the modem answers but does not establish communications.
Table 22 Controller modem troubleshooting
Modem does not answer
Cause Solution
Modem not powered. Apply power.
Modem not configured for auto answer. Check modem configuration and correct.
Modem not properly connected to phone line. Verify phone line is correctly inserted in modem
port and wall jack.
Bad cable connecting modem to phone line. Replace cable with known good cable.
Modem answers but does not establish communications
Cause Solution
Controller not powered. Apply power.
Modem set to wrong baud rate. Follow procedure to set modem to 9600 baud.
Modem configuration does not match specification. Follow procedure to configure modem. See
Remote Access (page 44).
Modem does not have non volatile memory. Replace modem with one of the recommended
types. See Remote Access (page 44).
Bad cable between modem and controller. Replace with a known good cable.
Wrong cable between modem and controller.
Replace with correct cable (not a null modem
cable).
Controller failure. Contact Honeywell service.