5 ton Brake Light

[holley68]

My M51A2 brake lights work, but the brakes will not turn them on. I haven't been able to track down a switch.

What signals the brake lights to come on when hitting brakes?

 

[Scrounger]

There are two types of switches, one hydraulic, the other air. Whichever switch you have will be under the cab by the master cylinder/ air pack. Without going back and looking, I think the ones that worked off brake fluid pressure were replaced later with ones that worked from air pressure. Something about when the brake fluid ones failed/ leaked it would cause loss of brakes.

Both switches have two connectors. Once you find the switch it is a simple matter of using a volt meter to check for voltage while soldier B presses on the brake pedal.

 

[holley68]

Scrounge, thanks for the reply.

I found the brake lights switch. It seemed ok, so I started tracking the wire back to the cab. It was cut near the cab. Had to add a little bit of wire, but works properly now.

Thanks