Found out to separate DRL function new wiring needs to be added. Grounds from new bulbs added to existing grounds near headlights.
The DRL relay in the convenience center switches between the 2 functions and powers the low beam tan wire(s).
Either with resister (DRL) output, or full power when headlight switch is turned on.
Arteb city light - severing the purple wire from near the relay (top middle pin)(99 Suburban) adding a relay for headlights (4 hi mod) to the purple. Purple near convenience center out to new relay location (86 coil power). I sealed the DRL relay end of the purple, no longer used. Left enough to splice back if desired.
Tan from DRL relay to drive city/DRL lights. New wire all the way to city/DRL bulbs.
Tan line splice was done underhood - cab side wire feeding DRL.
The other end, which runs to both low beams, now powered from the new relay (87).
Or could splice to purple if you don't want a relay.
Headlight wires run right past the underhood fusebox and ECU.
Tan low beams, lite green high beams.
I added a switch to shut off the city/DRL lights. Can do with the e-brake on a click
but i did not want to drive around like that, plus the light in the cluster then comes on.
From my notes bit of repetition here...
DRL module left side of steering column.
PINK is power from fuse
LTGRN/BLK is ground for drl relay and dash light terminal G 2 wires combined at module connection.
ON/OFF switch LTGRN/BLK to shut off DRL, lights and indicator.
Orange is input to resistor, yellow is out. Orange always hot, even with key off.
DRL relay switches resistor current, or headlight switch current, to tan wire (low beam headlight)
Relay input is purple from headlight switch, yellow from resistor. Output is tan wire to headlight (low beam)
I will say getting to that purple wire, without dismembering quite a bit, was a PITA, but can be done.
Adding relays is beneficial as it removes quite a bit of load/current traveling through the headlight switch, so it should last longer. A little less voltage drop to headlights as well.
The '4 hi mod' is pretty nice, and since you are messing around in there anyway...