Service lights do not illuminate in the Brake light position

[charlesmann]

I noticed since i got my truck, that none of my marker or park/run lights illuminate when the 3 lever switch is placed to the stop light position, but when placed in the drive position, all lights BUT my L and R park/run light illuminate when in svc/drive. Doing some troubleshooting and looking through schematics for the M939A2 series. It seems that at there is no power on wire #491, pin G at the cannon plug on the left side of the hood.

At the hood cannon plug, i have 25 volts to pins B and E which are for the headlights it seems. Following wire 491 back to the 3 lever light switch, it looks like it goes to pin L.

Has anyone opened the light switch, or is it sealed and not suppose to be opened?

Should any of the marker/park/running lights illuminate while in the stop light position? Its been over 10 yrs since iv messed with any military vehicles, other than my current MV and i can't remember if they are suppose to come on in the stop light position.

 

[charlesmann]

The standard 3 lever light switch does not provide a “parking lights” position. To get the parking lights/marker lights to illuminate you need to be in service drive(headlights on).

There are a few ways to modify your wiring to provide “parking lights. A bit of searching should yeaild some useful results.

As of now, its not that important for them to work out of svc/drive. I couldnt remember if they were suppose to or not, and you answered that for me.

 

[doghead]

Oop, accidentally deleted my reply.

at least it’s quoted above by you.