Where should I begin troubleshooting a Volvo A25C articulated hauler that has no brake lights or tachometer?

[Spencer Cawoddy]

I'm working on a Volvo A25C articulated hauler and currently have no brake lights and no tachometer.

I'm thinking it might be a shared issue like a fuse, relay, or ground, but not sure where to start.

• Has anyone experienced this on an A25C?
• Are these on the same circuit?
• Any common failure points I should check first?

Appreciate any quick tips before I dig deeper.