What does flashing red LED mean?

I have a flashing red LED on the printed circuit board - about 4 flashes per second - what does this indicate, please?

It is telling you the status of the sensors. Look in the instruction book. There is a chart!

4 flashes per second is not listed though. Maybe you have five flashes, or seven?

Thanks Mike.

Now I've read the handbook better, I realize the diagram showing the LEDs is a time-base chart. This might sound stupid, but I thought it was a diagram of LEDs on a board I did not have on my unit! Now it's all clear and had I realized this I would not have asked the question of you. Thanks for your patience. One other comment is that it's pretty difficult to count how many flashes are occuring in a second i.e. the difference between five and seven is hard to calculate whereas two flashes with a good mark/space ratio is easier. There's no critcism here of anything you've said, just that the designers may have overestimated the engineers' ability at visual precision!

Again, thanks for your help and for having this invaluable forum up there for us newbies.

(Changing both sensors worked well and the unit's running again)

:0) viking

I agree with the number of flashes being to much to see and count within a second.