I know I have read something about this question on this forum...but, right now I just can't find it.

I want to exchange the tail lights on my '04 for the newer look of the '06-10's. Three questions...
1. Is this just a "take one out, put the different one in" exchange or are there modifications that have to be made to the light to make it fit?
2. Does the top piece (the reflector?) have to be changed also or can the old one be used?
3. I think there is a different wiring harness for the newer light...is this correct?

Thanks for the info.

 

Here is the thread you're looking for, https://www.clublexus.com/forums/sc4...with-pics.html

 

I am having mine swapped out in a couple of weeks by the body shop painting my car.

1) You will have to swap out the ECU or deal with covering or ignoring a warning light. I splurged and bought the new trunk ECU.
2) The top garnish is different enough to where you can keep the old one, but it will look better if you swap it too.
3) Yep, you will need new wiring harnesses as well.

I wish I could do it myself or knew someone that could. I would rather have someone familiar with our car do it, with the ECU swap and all. Good on you for doing it yourself.

 

1. Yes just take out and put in.
2. The top piece should be replaced. it's a different tint of red and if you leave it there will be a gap between the two pieces. Also it has a slightly different shape. The newer one has a slight bulge.
3. The wiring harness is also different. It's the harness that needs to be unplugged from behind the trunk panel. Some replace the ecu but honestly if you can live with the light I wouldn't buy it.

 

Coleroad...thanks for the info. Just what I was looking for. Looks like no one has posted to this thread in a while. Anyone know whether there is updated info to any of this? Thanks again.

 

I don't know if you would call it "updated" but this is a similar thread with photos detailing installation from 2011.
https://www.clublexus.com/forums/sc4...cs-inside.html

 

Thanks sblevins...might not be much newer, but it is a darn good description of the process. Thanks for passing this info along. Guess I'm going to do this update...now all I need is $1,000 for parts.

 

Ok...one follow up question...hopefully someone who has actually made this switch can answer.
I am a little confused as to why you need the new "trunk computer" ($600) to make this setup work. Why can't you just buy the new tail light assembly and plug the old lights into it? Is it because the connection does not fit? Or is it because everyone is converting the new lights to LED lights? Seems to me that you should just be able to plug the old lights into the new assembly and avoid all of the "electronics" issues. But, if that were possible I'm sure someone else would have figured it out before me. Sure would like to have an answer if anyone has it. Thanks.

 

The trunk ECU basically removes the dash error warning light that would occur if you did the "simple" swap of the upper garnish and tail light assembly. Most just choose to dismantle the instrument cluster cover and use black tape over the warning light rather than spend the $600+ on the ECU.

 

Thanks, ShawnOK...but, apparently I did a poor job of asking my question. Let me also say that I have not yet pulled anything apart to see how these tail lights actually hook up and work, so my confusion may just be because I haven't looked at it yet. That being acknowledged, it seems to me, for example, that if you were only going to change a burned out tail light bulb, then you would just pull the connection out of the tail light assembly, put in a new bulb, and put it back into the assembly. The bulb doesn't know whether it is going in a 2004 assembly or a 2006 assembly and it would work just fine either way. Seems to me that both would have a "brake/tail" bulb and a "turn signal" bulb.
So, why can't I just leave the old wiring harness in place and insert the old harness and bulbs in the 2006 assembly? Is it because it will not fit? Or, there are more bulbs in the 2006 than in the 2004? Or, are the bulbs a different type (incandescent vs LED)? Or, what?
I am used to working on 50-60 year old classic muscle cars...these new things just confuse an ol' guy like me. Thanks for your response.

 

You're moving from bulbs to LED's if I'm not mistaken.
Different resistance causes the light out bulb to illuminate and the harness is different because the connector on the light is different.
It's been years since I did this to the SC I had so this is off memory.

 

Yes, the 2006+ tail lights are LED, not incandescent like the <2006. Therefore the harness changes. The Trunk ECU gives the system the "ok" that this decreased resistance is normal. Keeping the OLD ECU will trigger a fault that shows that a bulb is fused (due to the overall decreased resistance in the system which are the functional LEDs). Basically, long story short.. the NEW ECU is set at a lower overall resistance threshold and thus doesn't throw a dash error with the low resistance LEDs added to the system. This is the same idea with the aftermarket LED bulb swaps, now called Error Free, which guarantee that your car won't throw a dash light error b/c they are manufactured at the same or near to same resistance as the OEM incandescent which is being replaced.

 

See, what he said...

 

Ok...got all that. But, I still don't want to spend $600 that I don't have to and I would never be satisfied with the "black tape" solution. So, is there any reason that I would HAVE TO switch to LED's? Or could I just continue to use the old harness and bulbs?

 

You need the harness to fit the new lights and the new lights have the LED's built in.
That is the point of the conversion itself.