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I'm in the midst of designing a DRL setup for my 996.2 (which is a topic I recognize has been done to death). That said, I'm not a fan of LED light bars, and while I don't mind halos, this is a Porsche, not a BMW. Therefore, I'm taking inspiration from the Four Point Principle.
I'm using 8x total Luxeon Star 10mm square LED blocks, neutral white, with 10mm square Carclo 10415 elliptical-pattern lenses, and a 350mA FlexBlock on each side. DRLs should be on the order of 400 lumen per side and 1500Cd at the center, so I'll be using slightly lower currents than the LEDs are made for. As soon as I get dimensions 1,2,3 in the attached image, or even better a damaged 996.2 headlight unit, I'll figure out heat sinking, but it will be relatively unimportant at 4W per side, 150C maximum junction temperature, and 100F approximate steady state temperature insight the HID housing (per Pedro's Garage).
As far as wiring goes, here are my requirements:
DRLs turn on with the engine DRLs turn off with the low beams The low beams can be turned on whether the engine is on or not.
There are several ways to do this, of course, and I think I've picked the easiest:
1x Bosch relay with both NC and NO pins, connecting to 1x 928-610-511-00 relay carrier added to an open spot in the relay block Pin 30 connects to a fuse tap at A6 - Seat heater (switched on with ignition) Pin 85 connects to any conveniently-located bolt to chassis, possibly in the fuse box. TBD. Pin 86 connects to a fuse tap at A9 - Low Beam Right (switched on with headlights) Pin 87a is wired to the left and right FlexBlocks in parallel. Pin 87 is not necessary
The relays I have take about 150mA to switch, which *shouldn't* noticeably affect the low beams, but does put additional stress on the headlight switch. If that causes problems I might need to do the following instead:
2x Bosch relays with NC/NO pins Pin 30-1 connects to A6 Pin 30-2 connects to D5 - Cigar lighter (always on) 85-1 splices into 85-2, connected to chassis ground 86-1 splices into 86-2, interrupting the YE/WH wire running from the light selector stalk before it splits to go to A9/A10/Canada DRL block 87A-1 is wired to left and right FlexBlocks as above 87-2 is wired to the other side of the YE/WH split
Thoughts? Anyone have input on headlight switch reliability or wiring plans?