New to forum having just bought a dt175mx 1980. Back in the day I worked on these a lot so pretty comfortable with everything accept diagnosing electrics. And talk about bad luck, the headlights and tail lights stopped working at the MOT yesterday resulting in a failure
Have since discovered the lights are turned on and off at the ignition switch as well as the handlebar switch.  Will leave the post just in case there is anyone else out there as stupid as me and the MOT tester!

Edited October 31, 20186 yr by ajhuxley
no problem, discovered a 3rd key position to turn lights on

Yep, well known on here the weird world of why the F Yamaha did that.

Its not a bodge either its how they are. 

Hi AJ",,  yeh the second ignition position  brings in the Green/red  [ night time charging ],, as opposed to the Yellow lights to the switch, weird and wonderfull   A/c lighting eh,

 

thanks guys, btw does anyone have a wiring diagram for a late 1980 model (with square section swing arm). Ive got a Haynes manual to 1980 but I dont think the wiring diagrams are correct for my bike. (There seems to be a later Haynes manual that goes to 1985 but I dont know if this is worth buying compared to what I already have)

Cheers

This is the manual I have and it does have the diagram you want.

isbn 1 85010 300 3

thanks, found one on ebay