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    low-voltage troubleshooting

    Access control door will not release

    Common symptoms: maglock won't release; strike not unlocking; badge works but door locked; request to exit not working

    Stop and call a pro if:

    • Life safety egress must never be blocked
    • Do not defeat fire alarm door-release interfaces

    Step-by-step diagnostic flow

    1. Step 1

      Is safe egress blocked (occupants cannot exit freely)?

    2. Step 2

      Does the lock power supply show normal output and backup battery status?

    3. Step 3

      Does request-to-exit (button/sensor) trigger release when tested locally?

    Possible outcomes

    Stop — restore safe egress immediately

    high confidence

    Blocked egress is a life-safety issue and code violation.

    Safe next steps
    • Use emergency release per site policy
    • Notify safety/security lead and licensed technician
    Life safety egress impairment

    Lock power supply fault

    high confidence

    Failing lock PSU or depleted backup prevents expected lock behavior.

    Safe next steps
    • Repair/replace PSU and batteries
    • Verify fire alarm unlock relay interface

    Likely reader/controller logic issue

    medium confidence

    Local REX works but credential path does not.

    Safe next steps
    • Audit controller events and door schedule
    • Validate credential permissions and relay mapping

    REX path or relay wiring fault

    medium confidence

    Failure at local release path usually indicates wiring/input failure.

    Safe next steps
    • Inspect REX input and relay wiring
    • Service device with low-voltage technician
    Diagnostic guidance only. If unsure, stop and call a licensed professional — gas, electrical, and refrigerant work is hazardous to untrained users.

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