1986 300zx Brake light issues
 

Hi there ZDriver forums. This is my first post here, so forgive me if I break any rules in my post. I read the FAQ, I searched previous threads, but I couldn't find anything like the the problem that I am dealing with.

So I bought a 1986 Nissan 300zx around 4 months ago. It was supposed to be a fun project car for me. Well, I shouldn't have bought this car. It has issues on issues on issues. Still, I have had a fun time working through and fixing it as best as I can/could.

When I bought it, it had plates on it. Where I live safety/emissions is a must, so this means that everything was working. The kid (yeah, I said I shouldn't have bought it) told me that he had some electrical issues after installing his after-market stereo. I thought "Oh, a new alternator and things should be great".
Not so!

The brake lights don't work.
Not at all.

All other lights work like a champ. The headlights/brights/rear running lights/backup lights are all great. However, these break lights do not come on.

I have replaced the bulbs with the correct dual-filament bulbs. I have replaced the bulb casings. I replaced the stop-light switch. Nothing.

When I press the brakes, or turn on the lights, the "LIGHTS" warning light on the dash comes on. I read in the owner's manual that this is the "headlight and stop/tail light warning light" that should come on when I have a light out.

From my other readings, I believe that this means that I have an issue somewhere in the wiring.

I do not know where to look. Any advice would be appreciated. Thank you for your time.

the brake lights operate from a switch that is operated by stepping on the brake pedal. quite possible the meathead who installed his own stereo disconnected something or cut the wrong wire. get the fsm from xenon. use a vom or one of those neon light thingys to see if you are getting power to the socket. if you don't have a wife unit or buddy buy a piece of 3/4 pvc pipe (its cheap) you can then push on the brake pedal from the rear of the car with the lid open of course. then see if power is going to the switch. it should be hot all the time no ignition on or anything. blow up the circuit diagram in the fsm to 11x17 at kinkos makes it much more readable. start tracing wires.

Have you done the trouble shooting steps
 

The FSM for your calls for a test of the stop lamp sensor, your may be bad. It is in the el section, Exterior Lamp, Stop and Tail lamp Sensor Check, Page El 189 has the harness which shows that circuit and the sensor location,

Have yet to trouble shoot
 

Thank you both so much for the advice! I am busy all weekend, but come Monday I will test the stop lamp sensor and check to see if I have power and will follow up.

I didn't see the trouble shooting in the FSM, that really is super helpful.

Again, thank you so much for the help thus far.

Great. Report back and let us know how you do. :064: