I know I'm new here and don't have very much knowledge to the indepth parts of my Z but I own a 78 280z and I've had the brake light stick on before...I have reason to belive it is associated with being a check engine light as well as a brake warning light. So, with that said is there anything else going on with your car? Just another idea to think about.

There is no association whatsoever with a check engine light. The electronics in a 78 280Z, or any other year for that matter, are not that sophisticated. The brake warning light on your (and my or any) 78 consists of a warning lamp, a parking brake switch, and a brake fluid level switch. Problems occuring when the light is on in any system other than the brake system is purely coincidental.

sblake:

Yes my master was replaced by the previous owner, and it does have 2 wires that are attached to it, but they are just wrapped up and are not attached to anything. My mechanic could not find anything that they should attach to, this has puzzled me all along. In theory they should go somewhere, but they don't. There is a wire that is attached to the brake warning switch, but I cannot tell from where it originates.

I was looking through my stuff this morning and I found this. Don't know where I picked it up. I have amassed quite a few Datsun parts over the years. Don't know if it's good. Can't hook it up and test it since my 78 doesn't use it but if yours turns out to be bad you can give it a try.

I don't believe the 77z had wiring for low brake fluid. Just a wire to a switch to show an imbalance in brake pressure? That is what I originally thought my problem was. That is until one day driving with no passenger seat I tossed a tape mease onto the floor hitting said relay...the light went out immediately. :stupid:

We established that on the first page of this thread. 78 and up had the wired m/c caps, 77 and down had the switch I pictured in my previous post. He addressed the relay, also on page one. I was just letting him know I have the switch if he ends up needing it.

Fast forward 11.5 years later!!  This post still remains useful! My red dash break warning light issue turned out to be the relay under the passenger seat. Thanks!

On 1/22/2008 at 6:04 PM, TXZ1956 said:

I believe there is a relay under the passenger seat that causes this problem.

Yea, same issue with your old Z. 15 years later.