If I leave my Honda CRV outside at night, the emergency/brake light on dashboard
Stays on for about 3 miles until car warms up. I only use emergency brake while parked
On a hill so I have not had emergency brake on while parked overnight. It is an automatic. If I park in garage Brake light does not come on.
What will fix?:rolleyes:

The first thing to check is the master cylinder fluid level.

Master Cylinder fluid level OK.

Ok, Then the emergency brake lite switch. It's the switch that's activated when the emergency brake is on. Might be sticking.

I think you established that it's temperature related and it might be cabin temperature.

Where the brake fluid full level at and what is cabin temperature?

Rear Brake Lights (R/B/L) don't work when appling brake peddle, light bulbs and fuses are all good. (only checked some fuses, couldn't find "R/B/L" Circuits Number. NOTE: When I turn ON Headlights, R/B/L's come on', but don't light up when appling brakes. Have power going to brake peddle switch