Electrical Guru Needed for 1986 Daytime Running Light Issue.
 

My 1986 911 daytime running lights for the left front side and left rear side only turn on when the car keys are in the ignition in stage 1 and the right turn signal switch by the steering wheel is selected up to turn on right turn signal.

When the car is on and running and the driving lights are pulled to the on position the left side driving lights for the front and back do not turn on.

Is there an electrical connection in the steering column signal switch that can get crossed with the driving lights system?

DLRs on a '86 are an after market mod so who really knows how it was wired. Issue is likely in the frunk fuse box and not the turn signal switch. I bet that the DLR set up was achieved by moving around the bottom wires into different lower fuses. Daunting task. You need to print out the '78 color wiring diagram from our host tech articles which is quite close to the '86 insofar as the wire colors are concerned. Bentley manual is also a must ( but has some real shortcomings) to bridge the gap between the two years. If you want, I can .pdf you the relevant pages if you want so shoot me a PM with your email address.
Johan

Euro Cars had DLR option in the H1's. I have a notch for it in my H1's. Let's wait for OP to confirm if OEM or Aftermarket or just re-wired fog lamps to DLR.

86 has a one year only diode in the park lamp circuit. I can"t remember if left or right. There are more than a handful of posts that cover this floating around.. -J

DLR's
 

I don't think this is 911 has daytime running lights, the problem is the running lights. Only one side turns on when the car is running. I was going to buy a new dipswitch turn signal switch and replace that.

Answer may be in one of these threads
Pelican Parts Technical BBS - Search Results

Oh running lights, markers, open the lens and check for corrosion, clean and it should work, but before putting the lens back on check for voltage. Ground maybe dirty.

yes my 86 930 has (had) it. i removed it.
the reason i think it is there is for the park lights. you know, the ones where you tunr the car off then set the turn signal to left/right to turn on the park lights.
the license plate light is wired through one side of the lights for when the lights on turned on when driving, the diode keeps the license plate light from coming on with the park lights.
i dont ever use the park lights.

Vandal,
You need to read your PMs.
Johan