[Johnno SA]

Please who can tell me what is the connection between Gear selection and rear light function.
1990 1500SE

 

[Johnno SA]

Please who can tell me what is the connection between Gear selection and rear light function.

The grounds. I'm guessing your lights work when in neutral? Probably the gang connector on the left side of the frame about even with the front of the fuel tank. It's orange, taped into the harness.

The grounds. I'm guessing your lights work when in neutral? Probably the gang connector on the left side of the frame about even with the front of the fuel tank. It's orange, taped into the harness.

I have traced all ground lines from back to front, all relays work, no fault in multi ground connector.
Reverse diode and park diode are all good. all gear connections at engine control unit to ground are good.
I just cannot fathom what is wrong or links gears to back lights.

 

[Johnno SA]

Why don't you start with describing the problem?

After carrying out oil change etc. I discovered that the rear lights and flashers malfunctioned when any gear was selected. Everything worked perfectly in neutral. Select any gear 1st to OD and select left or right flasher apply brakes front or rear flasher stops and all back lights flash. hazards don't work either! Re select neutral and all systems work as they should.
Hence my frustration...

 

[Johnno SA]

Sounds like a classic ground fault. Shouldn't be that tough to trace with a multimeter. Do you have the wiring diagram?
Are there any aftermarket lights?

I have been tracing all ground wiring shown on wiring diagrams in my shop manual, using multi meter. At this time only the front fairing is on the frame.