Where is the Bulb-Out Warning Sensor?

Have high beams, no low beams. My switching relay works perfectly. It switches between the red (high beam) and gray (low beam) wires. Zero ohms on both paths, 12.6 volts on either wire when it is activated by the switching relay. Opened it up just to see how it works. All contacts look fine.

The gray wire goes from the relay to the bulb-out warning sensor, and from there to the low beams.

That leaves two possibilities:
1) a failure in or around the bulb out sensor
2) both low beams burned out simultaneously

I have not yet checked #2 because it seemed so unlikely, but I will check it while I wait for a response to this post.

CLUE - I replaced the radio on Saturday. If the bulb out sensor is in the center console area, I may have disturbed it or its ground.

Thanks!!

I located an orange plastic can-shaped 'thing' tucked under the edge of the dash, just above the knee bolster that turned out to be the bulb-out warning sensor.

The gray wire to pin #6 comes from my hi/low headlight relay, and gets 12 volts when the hi/low relay is switched to low beam. There is a blue wire to each headlight low beam. Pin #7 goes to the right low beam and Pin #2 goes to the left low beam. If I jumper from the gray wire to the blue wires, my low beams illuminate.

What are the chances of figuring out all the wires, and jumpering this whole stupid assembly out of existance? I fail to see the point of a warning system designed to alert me to a lighting failure, when the weakest link in the system is the warning system itself, and it CAUSES the lighting system to fail!!

Can the tail lights be simply jumpered around this thing, or is there something tricky going on inside it that will foul up my lights if I try to eliminate it?

I'd definitely jumper the gray + blue wires as you described to get the headlights working.

If a headlight bulb dies, do you think you'd notice it from the driver's position? I think you probably would.

I'd leave the rest of the bulb failure wiring intact, since all the rest of it is for rear lighting - when those fail you don't notice it as easily. The system does NOT monitor the small front "parking" lights, btw.

You definitely could bypass the rest of it also. It monitors the brake lights and tail lights.

Acording to Haynes:

Brake lights:
Power in - blue + red
Center - blue + black
Left - yellow + green
Right - yellow

Tail Lights:
Power in - white
Power in - green
Left out - red
Right out - brown
The two power in are for left and right, from separate fuses.
License plate lights are direct from fuse 15, not via the sensor relay.
--
Sven: '89 245 NA, 951 ECU, open-front airbox, E-fan, 205/65-15's, IPD sways, E-Codes, amber front corner reflectors. Wifemobile '89 245 NA stock. 90 244 NA spare, runs.

A little solder and shrink tube, and the sensor is by-passed and the low beam lights are lit again!

Bulb out warning light stayed lit for a second the first time I started the car after the mod, but not since then.

Could be my imagination, but it seems like the low beams are a bit brighter than they were before. I wonder if that sensor was introducing resistance into the circuit before it failed completely?