Detailed Answer
Pairing troubleshooting: 1. same frequency band for transmitter/receiver (433 vs 470MHz are not interchangeable); 2. button sequence (whether to press the transmitter pairing key or the receiver first, per the manual); 3. pairing time window (some models require completion within 3 seconds); 4. battery level (low transmitter battery fails pairing); 5. receiver in pairing mode. LDER one-key pairing: press both pairing keys on the sides simultaneously for 1-3 seconds. Still failing: restore factory defaults and retry.
| Band | Must match |
| Sequence | Per manual |
| Battery | Sufficient charge |
Note:Pair multiple units one at a time to avoid crosstalk.