just recently started upgrading the lights in my 96 sc400. I was looking at the daytime running lights and noticed they are not working in the front. Checked the light bulbs, they are good. Checked the fuse under the hood to find out that there wasn't one. Put in the 7.5amp hoping that was the issue, but it wasn't. I'm not electrically savvy by any means. Is there another fuse anywhere that I need to check? Or do I need to start chasing the wires? Any help would be appreciated.

 

I could be wrong, but my '96 SC4 didn't have DRL's... can anyone else chime in on whether or not they were equipped with them that year?

 

That would make a lot of sense. Like I said, electrical work and me are not friends.

 

In the USA, only 1999-2000 model year cars have functional DRLs. Your 96 only has some of the wiring, but not all of it. That's because all Canada spec SCs did come with DRLs.

 

Well son of a *****. That explains why they are not working lol. I feel stupid now. Thanks for the knowledge.

 

I just did a little searching on here, but never found a post where someone activated the DRLs on a 98 and older SC using OEM parts. ( I only searched for 5 min tho )
It appears that a lot of people rewire the fogs to be DRLs. Or install a DRL kit if their car requires DRLs. That's what Canadians do when they import a Soarer or SC from the USA.

I know some of the DRL wiring is already in US cars. But I don't know what parts are missing. I know the fuses are missing on mine, as well as at least one or two of the relays.

 

^^ You can check the electrical wiring diagrams for the 1999-2000 SC's and compare them to the 1992-1998 SC wiring diagrams and find the differences. That helps to establish what wiring, beyond just missing fuses and relays, needs to be added.

Then it is just a matter of looking up the headlight and DRL fuses and relays in the 1999 or 2000 SC300 or SC400 (or any Canadian SC model year) exploded parts catalog from a dealer parts website or on partsouq.

I haven't seen how an earlier U.S. model SC is converted to fully working DRLs with factory or aftermarket kit wiring but since the cars have some of the groundwork already present I'd think the factory method is the easiest and most foolproof approach.

 

Thanks Kahn. I agree with the factory way to go, definitely proven enough to be in mass production. I was doing a quick search this morning, I know these diagrams are on here somewhere but cant find them. Does anyone have the link to the wiring diagrams? I guess i'm getting a little education this weekend on electrical work!

 

I've got both of the specific SC headlight wiring TSRMs here for you to compare (USA spec non-DRL and Canadian spec with DRL). These cover the 1992-1994 model years but the circuits did not change throughout the production run to the best of my knowledge other than 1999-2000 USA models getting the DRLs standard vs Canada only for 1992-1998 models.

 

Now here's another thing I had not considered: how Lexus set up the required DRL circuits for their 90's cars was based around the stock 55W Halogen headlight bulb technology. Today though most of us use (or should be using) simply plug and play or fully custom HID headlight bulb & ballast upgrades for our SC's (brighter and safer compared to stock).

It is possible that the way the 90's SC300/400 stock DRL system (Canadian SC's and '99-'00 USA SC's) puts the Halogen bulbs into a lower wattage mode with dimmer brightness than normal when the DRLs are on could interfere or not work properly with more modern and superior HID lighting add-on kits. I'm not sure as I've never had to deal with it before but this does make me wonder what the best approach should be.

I haven't tested this myself but according to this video with a newer Lexus IS when we introduce the newer HID retrofit kits into our cars that originally came set up for conventional Halogen bulbs it all works fine on non-DRL wired cars but apparently there can be some flickering considerations.

Note: Disregard everything past the explanation at the beginning of the video. That's the only reason I posted it here. Our SC's are too old to use the Toyota TIS/Techstream connect-to-car system that allows this fellow to customize vehicle functions through his 2007 IS's OBD2 port.


This is actually a subject I may bring up to someone with some more electrical knowledge than me because I've been curious about doing this myself as DRLs are technically considered a good safety feature to have.

Below is also a video demo for one of the custom modified SC headlights that Organized Garage Status can do as a service which in this case includes a DRL option of their own design. Ultimately I'd be curious as to what their thoughts are on the original factory wiring for the 1999-2000 USA-spec SC's and Canadian 1992-2000 SC's as to how well all of that all plays with modern lighting upgrades from old 55W Halogen bulb technology.