Symptom → most likely cause
| Symptom | Usual suspects | Typical severity |
|---|---|---|
| Completely dark, no LEDs | 24 VDC supply, fuse, wiring — check these before blaming the panel | Often a cheap fix |
| Dark screen, power LED on | Backlight failure. Flashlight test: faint image visible → display works | Repairable |
| Touch unresponsive / drifting | Touch digitizer or its controller; application itself often still runs — dedicated touch guide | Repairable |
| Boot loop / stuck at splash | Corrupted firmware or application storage; sometimes recoverable via maintenance mode | Moderate |
| FATAL 3A at boot | Stuck touch cell detected in self-test — often something pressing the glass, not a dead unit: dedicated Fatal 3A guide | Often a cheap fix |
| Boots, but no PLC data | Network: cable, switch port, IP conflict, PLC path config — the panel may be fine: dedicated comms guide | Often a cheap fix |
Rule of thumb: check power, backlight and network before ordering hardware. Full triage steps: the 10-minute line-down guide.
Fix paths and what they really take
- Repair the unit (backlight, touch layer, PSU): typically $300–$1,000 and 1–2 weeks with a repair service — cheapest when the fault is display-related.
- Replace with a new PanelView Plus 7: lead times are commonly quoted in weeks and vary by model/distributor; budget extra time for transferring the panel application (.mer) and testing. Replacing a discontinued older unit instead? See PanelView Plus 1000 replacement options.
- Used unit: fastest on paper, but unknown service hours, no warranty, and you still need the application transferred.
Keep producing while you wait
Have the FactoryTalk project export? Drop it into our free HMI project converter — it runs in your browser, the file never leaves your PC, and your displays' buttons, indicators and values become app pages with the real tag names already in place. Graphics and alarm logic aren't carried over, and it takes the project export — a bare .mer runtime can't be converted.
Today, from a phone: the free LineKeeper Go for iPhone and iPad connects to your ControlLogix or CompactLogix over EtherNet/IP and reads the controller's own tag list — no export files, no configuration. Build a dashboard in about 15 minutes — the operator panel's start/stop buttons come once the right tags are identified, ideally mapped in advance. Mount a spare iPad in full-screen panel mode, and the operator has a screen before the first repair quote arrives. Reading is free; writes are a one-time unlock with confirmation and limit checks on every value.
A temporary screen in minutes
Zero-config tag browser for Logix, drag-and-drop dashboard, operator panel, alarms — no changes to the PLC logic.
On a desktop? Scan with your iPhone or iPad to get the free app.For the machine itself: LineKeeper On is a self-contained 7″ or 10″ touchscreen built to stand on the machine while the replacement panel is repaired or shipped — the same drag-and-drop screens, plus what a phone shouldn't carry:
- Live view of every mapped tag, refreshed twice a second — plus per-tag unlocked writes, confirmed and audit-logged
- Operator panel: start/stop, indicators, setpoints — hold-to-run releases when your finger lifts (not a safety function)
- Stays useful after the repair: data logging, dashboards, machine diagnostics
Small hardware that helps while the panel is out: a Wi-Fi bridge or a USB-C Ethernet adapter to get the phone onto the machine network, a pole-mount arm for the temporary screen, an IP67 box for the bridge. What each one is for, and when you don't need it, is on the gear list.