• Protip: Profile posts are public! Use Conversations to message other members privately. Everyone can see the content of a profile post.

brake lamp not working

14 July 2020
Sacramento California
1992 nsx tail lights work fine but when i press the brake nothing happens?

I checked the front fuse box and no fuses are blown

I checked if it could be the pedal switch, upon. Inspecting the pedal switch plug i see that im not getting any power.

The left side headlamp retractor isnt working anymore either but I haven’t tried to diagnose this yet.

And the spedo, fuel guage, and battery voltage on the cluster are not responding either.
Power for the brake lights comes from fuse #45 which is in the under hood fuse relay box (if that is what you meant by up front). Fuse #45 is powered up at all times. Pull the fuse and use a voltmeter to make sure that you have +12 v on at least one of the fuse terminals in the box. If you don't, then you have an up stream problem of some kind. If you have voltage at the fuse box, use the multimeter to confirm fuse continuity - visual inspection is not a guarantee if you have a fatigue failure in the fuse element. With testing, if you confirm that the supply to fuse #45 is good and the fuse is good, then you have a down stream problem. There are a couple of junction connectors between fuse #45 and the brake light switch.

Brake light supply.jpg

You will need to score a copy of the Electrical Trouble Shooting manual to find the location of those junction connectors.

The retractor motors are also supplied off of the 'hot at all times' supply; but, the speedo, battery voltage and fuel gauge are supplied off of switched power so it is not obvious that these problems are linked. Determining whether you have voltage at fuse #45 will tell you in which direction you have to start looking.