Hoping someone here has run into this. Setup: Qolsys IQ Panel 4 with an IQ Hardwire PowerG (the hardwire-to-PowerG translator that brings our legacy hardwired zones onto the IQ4 over PowerG RF), monitored through Surety.
Symptom: When the system is armed, we intermittently get a phantom entry-delay countdown / alarm on our “Back Door” zone in the early morning (~3 AM, roughly 4-5 hours after arming), while the door is physically closed. Last night the Alarm.com log showed: Back Door Opened/Closed → Pending Alarm (Awaiting Panel’s Programmed Delay) → Alarm → received by monitoring station. It was a clean open-then-close, not a stuck-open. The previous occurrence this year was on May 25; each time, power-cycling the IQ Hardwire PowerG module and the panel stops it temporarily and it returns months later.
What I’ve already checked on the sensor side:
Wiring: inspected the zone wiring end to end, all connections tight and correct, no shorts/opens or loose terminals.
End-of-line resistor (EOLR): confirmed the correct-value resistor is present and properly terminated on the IQ Hardwire PowerG input for that zone.
Sensor: physically confirmed working - the panel tracks open/close consistently with no missed transitions, and there are no trouble conditions (low battery / tamper / supervision loss).
Panel firmware is current (IQ4 Software Version 4.6.2, build rc0119_20260416).
Since the sensor, wiring, and resistor all check out and the panel firmware is current, I suspect the issue is on the IQ Hardwire PowerG side - i.e., the translator module or the PowerG RF link generating a spurious zone-open - rather than the physical sensor or the zone config.
Questions for the community:
Has anyone seen a phantom zone open/entry-delay that traces back to the IQ Hardwire PowerG (translator module or PowerG RF) rather than the sensor itself?
Did an IQ Hardwire PowerG firmware update, re-pairing/re-learning the module to the panel, a zone re-sync, or addressing RF interference/supervision permanently resolve it for you?
I’ve also opened a direct support request with Surety (asking them to confirm the IQ Hardwire PowerG firmware is current, check for RF supervision/interference or false zone-open events on the Back Door zone around the timestamps, and advise on re-pairing/re-syncing the module if needed). Wanted to ask here in parallel in case others have hit the same thing. Thanks!
I’m a little confused… I didn’t realize you could install a SEM on an IQ 4 Panel.
In any case, what is this wired door sensor connected to? Is it an IQ Sensor, PowerG sensor, a takeover module of some sort, etc? (Since the IQ 4 Panel has no hardwired sensor inputs.)
I ask because I’ve had this exact same issue with an IQ extended sensor ( QS1137-840) with a wired sensor attached to the external terminals. I had to replace the sensor. In my case I replaced it with a PG9945.
You’re right - the “SEM” reference was my mistake, and your question jogged my memory to go back and check what we actually installed ~3 years ago. Looking at our original migration-from-ADT shopping list, it’s not a SEM at all - it’s an IQ Hardwire PowerG (the hardwire-to-PowerG translator): Recommended Shopping List to Migrate from ADT Alarm/Pulse - #4 by jwcsurety
So to answer your question: the wired Back Door contact isn’t on the IQ4 directly (you’re right that it has no hardwired inputs) - it’s landed on the IQ Hardwire PowerG’s zone input, and the module presents it to the panel as a PowerG zone over RF.
Is it always the same zone/door that malfunctions?
I know you said you’ve verified wiring etc but I’d think this has to be a physical wiring issue, an eol resistor issue or even a bad reed sensor. I’d start with a fresh eol resistor for good measure.
I’ve also experienced this with a bad B connector from an old adt install. I had to re-terminate everything in the loop. (Wire tension on the b connector over time; buried in a crawlspace) in that case it was a window on a vista 20p system but same behavior)
Also - since you said it was a door is it possible the door or frame swells in the humid part of the night and causes the reed to be misaligned with the magnet? Just an additional thought.
Thanks, Darren - this is really helpful. Yes, it’s always the exact same zone/door (the Back Door) that malfunctions, never any other zone.
Given that it’s the same sensor every single time, I’m going to go ahead and redo the wiring regardless of what the testing has shown so far - re-terminate the whole loop end to end and drop in a fresh EOL resistor while I’m in there. Your bad B-connector story (re-terminating everything after wire tension loosened it over time in a crawlspace) is exactly the kind of intermittent physical fault that wouldn’t show up in a quick continuity check, so I’d rather just rule it out completely than keep chasing it.
The humidity/frame-swell angle is a great call too - these events cluster in the early-morning hours, so a door or frame swelling overnight nudging the reed out of alignment with the magnet fits the timing perfectly. I’ll check the reed-to-magnet gap and alignment (and reposition/replace the contact if needed) while I’m re-doing the wiring.
Thanks again for taking the time to share your experience - it’s genuinely appreciated.