Overview
MX974 pet-immune PIR motion detector for MX wireless intrusion systems.
Product type
Security sensor
At a glance
| Detail | Value |
|---|---|
| Category | Security sensor |
| Primary manual | MX974 MX PIR with Pet Immune Installation Guide |
| Install scope | Premises panel or bus device |
| Supervision | Panel trouble display when faulted |
What this device does in the system
Reports intrusion, life-safety, or status conditions to the host panel — faults appear as zone or module troubles, not always on the device itself.
Before you install or replace one
- Confirm exact model number on the label matches the install manual.
- Verify host panel or system family — Keybus, Corbus, Combus, PowerG, MX, or 433 MHz are not interchangeable.
- Check device limits on the panel/receiver before adding zones, sirens, or credentials.
- Include current draw in power budget calculations for modules, receivers, and keypads.
- For wireless: test RF at the mounted location, not only on the bench.
Official sources
- Product page: DSC MX974 - MX PIR with Pet Immune (ID 2723)
- MX974 MX PIR with Pet Immune Installation Guide — DSC official documentation
Troubleshooting
Quick diagnostic flow
- Confirm model on label matches MX974 MX PIR with Pet Immune Installation Guide.
- Verify host system in compatible-peripherals.md.
- Read active panel trouble (
[*, 2]) — note zone vs module vs low battery. - Check power and supervision at the panel/receiver before replacing the device.
- For wireless: test signal and enrollment at install location.
- For wired: verify EOL, polarity, and zone type programming.
Symptom-based fixes
| Symptom | Likely cause | Fix |
|---|---|---|
| Trouble immediately after install | Not enrolled / wrong zone type | Re-enroll; match zone definition to device |
| Intermittent fault | Marginal RF or loose terminal | Secure wiring; relocate wireless; check bus voltage |
| Works in test, fails in service | Placement or environmental | Final-mount placement test; adjust sensitivity |
| No alarm response | Programming / partition | Output mapping, partition assignment, bell enable |
Testing checklist
| Test | How | Pass criteria |
|---|---|---|
| Walk test | Panel walk test mode per manual | Zone activates and restores at panel |
| Wireless placement | Enroll-time placement test (IMPASSA [804], PowerG DLS) | Stable RF at mounted location |
| Tamper | Open cover | Tamper shows; restores on close |
| Battery | Simulate or wait for low-battery report | Supervision maintained after replacement |
After replacement
Re-enroll the device, re-test supervision, run walk test, and document serial/zone assignment for service handoff.
Source: MX974 MX PIR with Pet Immune Installation Guide; host system installation guide.