[Citroënbender]

A bit underwhelmed after getting to the bottom of this.

This is C69 per the wiring diagrams.

The large gauge yellow wire, is a power feed for premium sound, and power seats. The four smaller gauge wires are the pretensioners.

Never before have I seen a harness connector where pyrotechnics share with ordinary cabling. Given the corrosion to the large wire, what if it had "floated" and then made contact with one of the pretensioner wires? That could be a rather distracting outcome!

Glad I ran it down, now to fix...