89+ rear lights + 3 piece spoiler upgrade

[smagnotta]

Hello all,

I have an 87 Turbo manual, 87 stock ECU, and it had the old style spoiler with the rectangular 3rd brake light.

I first upgraded to the 89+ rear lights and center piece and that worked fine with no errors for 3 years.

My latest upgrade was the 3 piece spoiler, and after installation I am getting the rear brake light sensor failure light on the dash.

All the lights work fine, however. The 2 brake lights come on each side when I press the brake, the right and left turn signals work, and when I put the car in reverse the 2 white lights come on. The hazards also work. The 3rd brake light also shines when I press the brake. I took the bulb holders out of the lens housing and watched which lights came on as my wife was in the driver's seat.

The brake sensor failure light appears the first time you press the brake after ignition.

I replaced the light bulbs (with new ones) and the yellow sensor with a different one and am still getting the error.

The multimeter test on the plug that goes into the yellow sensor passed.

Is this error due to the new spoiler having a LED brake light instead of the old block one?

 

[NecroCyde]

Hello all,

I have an 87 Turbo manual, 87 stock ECU, and it had the old style spoiler with the rectangular 3rd brake light.

I first upgraded to the 89+ rear lights and center piece and that worked fine with no errors for 3 years.

My latest upgrade was the 3 piece spoiler, and after installation I am getting the rear brake light sensor failure light on the dash.

All the lights work fine, however. The 2 brake lights come on each side when I press the brake, the right and left turn signals work, and when I put the car in reverse the 2 white lights come on. The hazards also work. The 3rd brake light also shines when I press the brake. I took the bulb holders out of the lens housing and watched which lights came on as my wife was in the driver's seat.

The brake sensor failure light appears the first time you press the brake after ignition.

I replaced the light bulbs (with new ones) and the yellow sensor with a different one and am still getting the error.

The multimeter test on the plug that goes into the yellow sensor passed.

Is this error due to the new spoiler having a LED brake light instead of the old block one?

sounds like you need the 89+ tail light failure sensor. did you install it? its a yellow box on the driver side just under the inside of that tail light.

 

[smagnotta]

sounds like you need the 89+ tail light failure sensor. did you install it? its a yellow box on the driver side just under the inside of that tail light.

Wow, dummy me, I used an 87 yellow box instead (my original old one and another one).

So I am assuming the boxes differ from pre 89 to 89+ ?

So will the 89+ yellow box correct the problem? Won't my 87 computer trigger the failure light anyway?

 

[lewis15498]

If you cant get the failure box to work, heres how to remove it:
http://www.supramania.com/forums/showthread.php?t=82576

FYI: this should be in the General MKIII discussion and not the 7MGTE Tech

 

[smagnotta]

It's a sensor failure/electrical so it's technical not general in my opinion, but no prob. Thanks for that link -- I've seen that before...

 

[rayall01]

Yeah the led's signal is different from the old style light, so you definitely need the correct sensor, or bypass it.

 

[smagnotta]

Thanks all who responded; it makes sense.

Get a new failure box (89+ one) or rewire.

 

[smagnotta]

Update: I checked with Toyota and there are 2 possible brake light sensor failure boxes:

86.5 to 88

and

89 to 92

Two boxes.

The same part number for 89 through 92.

Also, it looks like the brake light lens and bulb holders are compatible through the 89 to 92 years...

 

[lewis15498]

General MKIII Discussion: Discuss everything relating to the MKIII that isn't technical engine talk. That would include this. No big deal tho.
Anyways, if you choose to go with a rewire, feel free to PM me with any questions, I wrote that thread.

 

[Poodles]

Thread moved.

Also, it's because the LED's don't have enough resistance for the circuit so it sees it as a blown bulb, you can modify the box with a different resister IIRC or just get the right box.

 

[Rob_Supra87]

So Im interested also in the 3 piece spoiler so im just curious, can I just not put in that wire for the brake light on the spoiler and just black it out? I plan on putting a black spoiler on mine, or will blacking it not look good?

 

[RazoE]

just swap the box to an 89+ TURBO box, which is an ivory color, compared to the yellow box for all 86.5-88 Supras, and 89+ NA Supras without wings...

as for the 3rd brake light, when you install a wing, it is 100% plug and play, just unplug your old 3rd brake light, and plug it into the turbo wing and the LED bar will light up, unless SOMETHING ELSE is wrong..


and Rob: European supras had the 3 piece wings WITHOUT the 3rd brake light, so that's something you might want to look into..

 

[Poodles]

Personally, I like the brake light on the 3 piece wing as it's a nice bright LED strip...

 

[smagnotta]

Just as a follow up, I used an 89+ brake sensor box (in this case it was ivory colored) and it worked just fine. The light went off on the dash. Thanks to everyone who replied.