My first post here so bare with me!

We have a trx90 which does not display the green neutral light when in nuetral and wont start on the button. If we bridge the starter solenoid terminals she fires up!
The neutral safetry switch has been swapped off another and we know it works and it still does the same.
Of note on the left bar switch if we flick left or right on the engine stop switch the neutral light works.
Wiring has been checked and we have continuity for the switches. Any ideas?
Likewise on kne of our trx 250 sports.
We have had a auto electrician look at it and he is baffled…..