Five 9s Communications · Field Service

Emissions Terminal
Network Troubleshooting Checklist

Utah DMV Connectivity — Site Investigation
Checklist Progress 0%
L1 Physical Layer
Inspect NIC link light on emissions terminal
Solid = link present · Blinking = activity · Off = no link
Trace and inspect CAT6 run — terminal → switch
Look for kinks, tight bends, crushed jacket, loose RJ45 boot
Try a different switch port for the terminal connection
Swap patch cable — terminal to wall jack or switch
Check switch → router and router → modem cables
Verify Comcast modem "Online / WAN" indicator is solid
If modem is not online → Comcast provisioning/outage issue
L2/3 Local Network — IP & Routing
Run ipconfig /all — record IP, gateway, DNS
⚠ 169.254.x.x = APIPA — DHCP failure. Check switch/router.
Ping the default gateway: ping <gateway IP>
Failure here = cable, switch port, or router problem
Ping public IP to test internet: ping 8.8.8.8
Success = physical + ISP OK. Problem = DNS or app layer.
Check current public (WAN) IP address
Google "what is my ip" from the terminal's browser
⚠ Compare to what Utah DMV has whitelisted for this location
DNS DNS Resolution
Resolve the DMV hostname: nslookup <DMV hostname>
Failure = wrong DNS servers configured, or DNS blocked by firewall
Verify system clock is correct (date & time, timezone)
⚠ Wrong clock = silent SSL/TLS certificate failures
FW Firewall & Port Connectivity
Obtain the DMV connection IP and port from Utah DMV tech or emissions software config
Test port reachability:
Test-NetConnection -ComputerName <host> -Port <port>
Blocked = router ACL, Windows Firewall, or Comcast business blocking that port
Check Windows Firewall on the emissions terminal — confirm no outbound rules blocking the DMV connection
Log into Comcast/router admin — check if the port is blocked or if there is a firewall rule denying the DMV destination
ISP ISP / Comcast Business
Confirm with Utah DMV — what public IP do they have on file (whitelisted) for this Grease Monkey location?
⚠ If this differs from the current public IP — IP whitelist mismatch is the root cause
Verify account type: Comcast Business (static IP?) vs. dynamic IP
Dynamic IP + DMV whitelist = common recurring failure point
Check for Comcast service outage at this address
Check Comcast outage map or call Comcast Business support
APP Application & Software Config
Check emissions software config files for hardcoded IP addresses or server hostnames — verify they are current
Check for proxy settings configured in software or Windows — confirm they are valid or disabled
Check SSL/TLS certificate validity on DMV connection
Browser warning or software error message about certificate = cert expired or clock mismatch
Review emissions software error log / event viewer for specific connection error messages
INFO Key Contacts & Info
Utah DMV Emissions Tech Contact
Comcast Business Support
Business support: 1-800-391-3000