Xantia 2.1

There's no power to the instrument cluster, multiple faults, the speedometer, trip odometer, and glow plugs aren't working (the indicator light isn't working and the glow plugs aren't activating), nor are the turn signals or the malfunction indicator light. All fuses have been checked. This coincides with a broken serpentine belt.

Checking the battery is the first thing you should do.

The battery is fine, and I've also checked the fuses both inside and in the engine compartment. I'm a bit puzzled by a relay inside the control unit box; it makes a clicking noise when I press fuse number 5 in the engine compartment, and the vehicle stalls.