Fitting Philips DRL 8's into A3 Fog lamp surround trims

I found this this thread really useful when looking to fit DRL's.

I personally prefer DRL's to be located away from the main light units to avoid confusion with indicators, etc. so like the fog-lamp grill location. Clearly Audi designers don't agree with me on this point and are probably better qualified than me to comment on the issues of safety surrounding distraction caused by DRLs.

Anyway, the Philips DRL 8 units fit neatly into the fog-lamp surround slot (pre facelift model), and the LEDs and electronics are of a good quality as you'd expect from an OEM lighting manufacturer like Philips. (Dectane do a nice pre-moulded set but, having tried 3 sets, my experience was that the electronics were not very reliable).

I fitted mine with the lens flush to the edge on the fog-lamp trim moulding (pictures within thread), so they would get cleaned in the car wash, however others counter-sink them back into the moulding which requires cutting the back out of the trim rather than just drilling a hole. Both options described in the thread.

It's a straightforward install as detailed in the thread, and mine have worked faultlessly for a couple of years now.


Philips LED DRL- a good alternative if you want OEM performance and output...

No, there is no coding to do at all, the Philips control unit is completely stand-alone from the ECU.

My simplistic understanding of how it works is that the ECU senses a "voltage drop" or some similar voltage signature from the altenator when the engine is running and switches the DRL's on. When the engine is switched-off, and the battery voltage stabilises, the DRL's automatically switch-off.

There were some comments on the thread about the DRL's flashing when doors are unlocked, etc., creating a voltage drop in the battery. For this reason, instead of connecting the live feed directly to the battery as recommended in the instuctions, I used a piggy-back fuse to connect to the Glow Plug Circuit in the fuse box which the ECU powers down about 20 seconds after the engine is turned off. This also means that if you are parked, but want the electrics on to listen to the stereo, etc, the DRL's don't have to be on. This set-up has worked well, and I haven't noticed any silly flashing on & off at the wrong time. There is also no flickering of the LED's on start-up which you sometimes get on cheaper quality units, so the Philips items are good quality as you'd expect from Philips. Full write-up and photo of fuse box connection if you scroll through the post to page 2.

The earth connection from the Philips control unit can be made at the earthing point just behind the battery (to the left). The Dectane installation video referenced in the link is actually really useful in showing you how to remove the fog-lamp trim, and where to route and connect the wires specifically on an A3, the Philips video is more generic though does feature a face-lift model A3.

Another wire from the Philips control box connects to the side-light circuit wire at the connector on the back of the headlamp, so when you turn your sidelights on it automatically dims the DRL's to be legal. I'd actually have prefered them to switch-off completely when the headlights are on, but this isn't an option on the Philips DRL 8. Dimming does seem to be the 'fashion' with new cars, and isn't really a problem other than the LED's are a slightly bluer-white light than the original sidelights yellow-white light so don't match - I resolved this with a pair of Philips W5W blue-white side light bulbs which give a better (if not perfect) colour match to the front of the car. Alternatively, within the DRL 8 box Phillips supply 2 blanking resistor "bulbs" for the side lights; these don't give out any light (as technically for the purposes of the MoT your dimmed DRLs are acting as your side/positioning lights) but the resistors prevent a blown-bulb warning showing on the dash as it would if you simply removed the sidelight bulbs.

Given that these DRL's are located well away from the main lights and indicators there is no need for one side to dim ("wink") when the indicator on that side is operated - which to my eyes is a very good thing!

Once installed, they are fully automatic and you don't have to switch them on or off. They come on when the engine is started, dim when you turn lights on, turn-off 20 seconds after you switch the engine off. Pretty much like an OEM set-up and fully MoT compliant.

I've had mine on for a couple of years with no problems at all.

Neil C said:

Was there any coding to do after fitting ?

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