I own an '85 XJ-S HE, I noticed today when warming her up that when I applied the breaks, my front driver's side signal came on - not flashing as if I was about to make a turn mind you but steady - as if it too were a brake light. I recently got a new EMS installed, and soon I'll have to change my battery; I suspect it may be a fuse, any thoughts?

 

As with your other previously reporting lighting problem, the best place to begin is by cleaning all relevant grounds and bulb sockets.

In fact, I suggest you clean any and all grounds and wiring connections as come across them while working on various parts of the car.

Goods to check fuses, of course. Sometimes a blown fuse can cause weird feedback issue. Rare, but it happens. Clean fuse clips/contacts while you're at it

Cheers
DD

 

Right then, I'll have to start there as you mentioned before, and I'll report back if anything else changes. Thanks again!

 

What is an EMS please?

 

UPDATE: Firstly, let me apologize for getting back to this thread so late! The Holidays have had me swamped. Anyway, so what happened was after I cleaned out some of the bulb sockets, it turned out I also had a bad battery (The wrong type, the genius who owned it before me really didn't care about her too much!) After getting that replaced, a gentleman at my local Interstate Battery pointed out that some of the fuses were blown and needed to be changed. After a quick fuse change, the blinkers and brake lights are working right as rain now! However, as any XJ-S owner knows very well, sticks and stones may break my bones, but there's always something on an XJ-S to fix!