Hi 👋 I have a 2006 maxima and all 3 brake lights stay on. I have tried replacing and disconnected the brake pedal switch and the cruise switch and they still stay on. If I push on the brake pedal they seem to get just a touch brighter. I tried pulling the lamp fuse in the engine bay and under the steering wheel but they just won't shut off? Any ideas 💡 thanks 🙏

 

It looks like they get power (at least some power) from something they should not.
From the stop lamp switch to the stop lamps, there are M81 & M90 connectors (see service manual LT-133).
You should check the voltage at the corresponding pins.

You sure the stop lamp switch works properly ?
Did you check the voltage at pin 2 with the brake pedal released ?

 

So I double checked and the brake switch does work. if I remove the "bat 10a electronic parts fuse" they work perfectly fine, off with no brake push and on when you push the brake brake pedal. Could it be just bad bulbs? I'm not sure how to check voltage I'm a total noobie at that. I just got a multi meter and barely know how to use it, if the fuse when plugged in makes them come on is that considered "a short". With the fuse in if I hit the brakes the bulbs go just a tiny bit brighter if that helps any, thank you.

 

The BAT 10A Electronic parts fuse is fuse 12. It gets power through the ignition switch only in the On & Start position.
When the car is off removing it should have no change.
The fuse 12 is a *****, it feeds a lot of stuff.


Option A:
I would find the M90, M81 and B131 connectors to disconnect them one by one in order to limit the possibilities.
For example, find and disconnect the M90 connector and see if the brake lights turn off.

Precision: the 3rd brake light will turn off when you disconnect the B131 connector.


Option B:
if the connectors are to hard to access or find, I will check the wiring diagrams of the parts fed by the fuse 12 in order to notice the ones which share M90 or M81 or B131 connectors.

 

I have the traced the wiring from the brake switch all the back to the twilight. There are connections right next to each tail lamp and right under the center brake light and when I disconnect them the lights goes out for each individual brake light, I have read the ipdm receives power from that fuse and may be bad. Also I heard there may be a stuck brake relay there but have no clue as to where? Thank you for help!

 

It's strange but with fuse 12 bat 10a fuse removed it seems like everything works normally. I will wait for your diagram if you can find it but it seems like it just doesn't want that fuse or need it? All the lights seem to work including the sunroof. The prior owner said there was some type of abs issue with it the abs kicking in while driving maybe it could be related to the lights? Thanks again

 

I take that back the lights don't work without fuse 12 or it looks like fuse #19 on one of the diagrams online.

 

I disconnected the ipdm and fuse box next to the battery and still the lights stay on, the bcm and box next to it were also disconnected with the same result, I can't seem to find the m81 and m90 connections. Thanks

 

You can download the service manual here: http://www.nicoclub.com/archives/nis...e-manuals.html

 

It was a dime inside the unified amplifier.. works fine now, thank you for your help.