A riddle for some bright spark to solve :-)
We have four outdoor lights which are linked to two PIR sensors, and controlled by a single light switch in our hallway. They worked fine for the first 8 months we have lived in our house, and then about 6wks ago we found that they stayed on permanently (day or night) and therefore we had to trip the circuit breaker in the fusebox and leave the off to stop the lights being on.
Today we replaced both sensors. The good news is that the lights will now switch off using the light switch. However, two problems remain. (1) the sensor never switches off the lights, they stay on unless you switch off using the light switch. (2) if you leave them on for any more than 5-10mins then the light switch stops turning them off, so you have to trip the circuit breaker on and off at the fuse box, and then they respond to the light switch.
Totally baffled by this, but hope this is something really simple to sort. Any suggestions???