Today I decided to install a daytime running lights module that activates the high beam headlights at about 30-40% power. Unfortunately, in my country, there's a law requiring the use of headlights (low beam or daytime running lights) even during the day, which is annoying in the case of the Gen1 because it significantly dims the speedometer. I can brighten it with the button under the LCD display (where the US versions have the mph to kph button), but it still doesn't fully brighten the speedometer as when the headlights are off. Never mind. While trying to connect the DRL module, I discovered traces in the wiring diagrams and in the fuse box under the hood on the driver's side that suggest this model might have factory DRLs. Take a look at the photo. Point 1 shows the relay socket. According to the diagram, the version with DRLs should have a jumper. Point 2 has a jumper or some kind of pin protection. According to the diagram, the DRL should have a 30A fuse. There's a jumper in point 3, but there should be a dimming relay (does anyone know the part number?) I'm missing two fuses in point 4. I've circled the low beam fuses in blue because I had a question, but I already found the answer myself, so don't mind. And now the main question: Is there a chance that after filling in the missing parts in the box, I'll be able to activate the factory daytime running lights? If so, I won't bother with any additional DRL modules. Or maybe something else is missing.
I got excited too quickly. I've been poring over the diagrams and I already know it won't work (if anyone wants to see for themselves, it's in the first post in the PDF file from page 80 upwards). Even my DRL module won't work either. It turns out that the beams in both versions are completely different. So much so that the version with DRL has a bulb with a constant ground (the dimmer is on the ground side), and the high and low beams are switched by 12V. The version without DRL, on the other hand, has a constant 12V on the bulbs, and the high and low beams are switched by ground, which completely disqualifies my DRL module, which requires a constant ground. So I'm stuck with a crappy LED DRL in the bumper.
More sunny days have arrived, and driving with a dimmed speedometer has become a nuisance (as a reminder, in my country, headlights (low beam or DRL) are required to be on all day, not just at night), so I decided to revisit the issue without the ugly LED DRLs in the bumper. My idea was to use (in addition to the DRL module mentioned in the previous post) an additional H4 headlight harness with relays from Aliexpress and connect the DRL module to it. This harness is usually used to improve or repair stock headlight harnesses in older cars with significant voltage drops. The stock harness then controls only the relays, and the full load from the bulbs is transferred to the relays. For this harness, it doesn't matter whether it has a constant ground and positive control or the other way around, i.e., constant 12V and ground control. At the output of the harness, it receives a constant ground and positive control, which was required for this module. An additional advantage of this solution is minimal interference with the stock harness and a virtually fully reversible modification. The only modification required is a small cut in the fuse box to route the wires and solder a wire to the left parking light bulb to provide a signal to turn off the DRL module. If this Chinese harness or DRL module fails, I simply reconnect the H4 connectors on the bulbs to the stock harness, and the problem is solved. The first photo shows the harness and DRL module. The second and third photos show them connected together (I additionally sealed the DRL housing with RTV and tape). The fourth photo also shows where the main power supply for the harness comes from (red wire). This is the same electrical circuit that powers the headlights from the stock harness. The harness on this wire has its own fuse (black housing on the left). The orange wire is simply the 12V signal for the DRL module when the ignition is on. The DRL module activates above 13.2V, meaning if charging doesn't occur, it remains in sleep mode. The ground for both plugs is taken from the stock ground points on the front fascia near both headlights. The module is set to 40% power. You can reduce it to 30%. I used this setting once in another car because it had new headlights, and 40% was a bit blinding to other drivers (remember, I'm using a high beam bulb). A video showing how it works. Link to wiring harness https://www.aliexpress.us/item/3256808914602109.html?spm=a2g0o.order_list.order_list_main.47.54391c248OHSS9&gatewayAdapt=glo2usa4itemAdapt My DRL module is a local product available only in Poland, but I found an alternative, albeit with fewer features. The CD0103 module is linked below. https://www.aliexpress.us/item/3256806418603891.html?gatewayAdapt=glo2usa4itemAdapt
