[FrankM_]

@Ray911
Installing the relays won't fix that issue as you are mostly reusing all the wires that are in the car to switch the relays on/off, so if you have a problem there, it gets 'ported' to the new situation.

I like the idea of timmy2, I hadn't anticipated that the jumper/bridge could fail but it certainly can become loose or oxidated. As timmy said, use a short wire to make a temp jumper on the top of the 2 fuses and check.

If that doesn't fix it, jou will have to use an Ohm meter to check the wires running to your non-functioning light. Especially from fuse 4 (right light) a yellow wire (MY88) should run to the headlight. Measure it (power off) with an ohmmeter on both ends to see if the wire is uninterrupted. Then you know it is not the bulb, nor the wire running through it and it has to be fuse / bridge related (where left and right circuits split).

When checking the fuses, do get them out, clean the contacts and reseat them, do not only visually inspect them.