My tail light, number plate light and the dash lights are not working. I know that they are all on the same circuit, most of the bulbs are new, I think only one I have not replaced. The brake light works, I have checked all the fuses and connectors and everything looks good. so what else do I need to check?
An intact fuse is not one that is necessarily making full contact. It needs to be dead flat with no twist to make fulll contact with the holder and it needs to have no light oxidation between it and the holder. So, make sure it’s flat and give it a jolly good wiggle.
I have, and the main lights, indicators, information lights on the dash and brake light work, which I think are in the same fuse.
Have you changed the Rev counter loom recently? There are a couple of different looms and when I changed one on my P8 ecu 916 it caused all sorts of weird symptoms.
All the original loom. The fuel pump is not connected at the moment but I can’t see how that would affect things. If you look on the wiring diagram, I think it’s the yellow cable that’s causing the problem.
Hmmm, poor earthing can cause strange problems. Multimeter and test light on your yellow wire? @Derek ???
Didn’t think to check the earthing. I get a reading on the meter when I turn the lights on from the yellow wire, so something is happening. I’ll check the Earth points again tomorrow.
Madge, get a length of wire and short between the battery - post and the shell of the lights, that will confirm an earth breakdown and takes a few seconds to diagnose. Carefully check the round connector under the front rhs of the tank for an dirty or burnt pins, also the three way connector for the ecu under the seat (this earths the back end of the bike). Clean the ignition switch (use contact cleaner down the key slot) and check the ignition switch front loom connector plug. Hope its easy to find
All the contacts have been checked and cleaned, didn't think of putting contact cleaner in the key slot. I'll check the earth point later, but if it was a bad earth then I would have expected the brake light and indicators to not work as they come off the same earth.
Solved. It was the big round one on the rhs coming up from the battery. I must have missed it as once I cleaned it with contact cleaner everything worked. Also gave the ignition switch a blast of cleaner as well, as I assume that inside must be a bit mucky.
