TR brake light flickers, stays on, flickers

Try setting and releasing the parking brake. If the handle isn't proper it will cause the light to remain on and possibly as in your case, to flicker. It's one thing to check that you haven't mentioned.

 

Jay -- Just to confirm -- You do mean the small round brake warning light in the top-middle of the Driver's instrument display?

If so, I'll take a peak at the TR wiring diagram tonight to see what's involved. Since you've been in to check the fluid level you've probably already done this, but do confirm that the wires going to the level switch on the reservoir aren't fouled in the wiper mechanism or the brake pedal lever mechanism.

PS IIRC the small round brake warning light is only controlled by the level switch on the reservoir -- it doesn't indicate anything about the pads themselves.

 

Steve, as I indicated above an incorrectly or not properly released brake handle will cause illumination of the warning light. At least it does on my car

 

Jay -- The bad news is that there is maybe a plausible explanation for your symptom, and it involves an "ECU". Per the TR wiring diagram, the brake warning light is controlled by either the level switch in the brake fluid reservoir or by a small ECU called something like a "seat belt buzzer" or "seat belt controller" -- item 13 in the jpeg (mounted behind the fuse-relay panel). But regardless of the name, it also runs the "self-test" of the brake warning light at start-up.
The way the system works is that the "+" side of the warning light bulb is always at +12V. If the brake fluid level gets low and the level switch closes then the "-" side of the warning light bulb is connected to ground and the bulb glows. However, when the ignition key is placed in the "start" position, a +12V signal is given to the seat belt buzzer item 13 via the B (white) wire which then connects the N (black) wire going to the "-" side of the warning light bulb to ground (so the warning light comes on whenever the starter motor is cranking just as a self-test to confirm that the bulb is OK).
Best case, you have a bad connection at item 13 that is somehow intermittent. Worse case, something inside that item 13 seat belt buzzer ECU is truly frazzled and is wrongly putting a ground signal on the N (black) wire when it shouldn't be. You might try just unplugging item 13 and see if the false warning light events stop occurring (assuming the seat belt system can work OK with that buzzer/ECU unplugged). If the connections look OK and unplugging item 13 stops the wacky indications and you always get the bad indications when item 13 is plugged in, I think that would confirm that item 13 itself is toast. Also, is the self-test working well? -- i.e., does the warning light always comes on just after initiating starter motor cranking and go out properly? Not getting the warning light "on" during some starter cranking events would also be a bad sign for item 13.
Anyway, that's my understanding of the situation -- give a shout if you need something else and let us know how it works out.

PS I should correct an earlier mistake -- the red warning light is rectangular. It's the symbol printed on the light that is roundish.
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Reviving this old thread. The brake fluid warning light has been on for a while. The fluid is fine. A couple of times I was able to make it go off by pressing the little plastic dot on the fluid reservoir but now it doesnt seem to do the trick.

I opened up the fuse box to check item 13 that Steve mentioned but it does not exist on my 87 Testarossa version.

Any other items I can check?