Daytime Running Lights (DRL)

Hi - this is my 1st post here.

I have a '93 J30; the driver side running lights do not come on. I have electronically bench checked the DTRL relay in the fuse box & it works as per the schematic. The headlights work as req’d for lo-hi beam. However, a weird thing came to my attention in another US forum; removing the DTRL relay does not affect them working; the guy in the US, hoping to disable them, removed his DTRL relay with no change; I did the same, no change - ds still out, headlights work so wtf?
The gray box on the fender well is the DRL actuator; if you remove one of the 2 plugs, one side of the headlights is totally deactivated.

I’ve been told, the headlight relay is on the FireWall, a black disc on the firewall near the brake “booster”. I didn’t spot it when I looked for it. Can anyone be more specific, like diam in inches, higher’ lower, right-left as you look at the F/W?

i cant help but i am going through a similar situation in an S14… massive pain in the ass.

I’m calling the gray box on the fender-well the mystery box, because I think the prob resides there, but the schematic diagram in the working manual does not show its internal wiring, hence my label. I think some sh*t like a desoldered connection happened in there, but the box appears disassemble-proof in order to get at the circuit board therein. I tried, but couldn’t figure out how to remove the smaller plug; the bigger one was easy. The enclosure is heavy-duty sheet metal & even if you figure out how to remove the smaller plug, you gotta then figure out how to get into the recessed enclosure. I gave up.

I forgot to mention, someone told me this is is DTRL “actuator”.

check if you have a fuse for the DRL usually Nissans and Infinitis have bith: a relay and a fuse to control the DRL
Let me know how it goes