1999 cougar brake lights not working Fuse+bulbs+switch ok

Since the turns work in the back, that means the brake bulbs are good. Brake lights and turn signal lights share the same filament in the bulb.
There is a fuse for the brake lights. Then, there is a brake light switch on the brake pedal. You need a voltmeter or test light, after checking that fuse is good. Need to check if fuse has power on it. This is one of those fuses that are hot at all times-as long as battery is connected, voltage should be going through the fuse and up to the brake light switch. Check for power both places. The switch on the pedal is a simple on-off switch. When brake is depressed, the spring loaded switch is turned on-passing power on towards the brake lights.
But then the brake wire goes into the turn signal switch before going on to the brake bulbs...however, since your turns work good, I doubt if there is a problem in the turn switch. First check if the brake light switch is sending power on when switch is on.
Let me know what you find. Good luck.

Check fuse 24 in the interior fuse block. If that's good check the brake switch. There should be power on the violet/white wire all the time. There should be power on the green/orange wire when the brake pedal is depressed. If there is no power with the brake pedal depressed than the ditch is bad. Let me know if you have any questions and I'll do my best to answer them. Thank you for using FixYa.com!

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

assuming the bulbs are ok ,has to be the brake switch,on the pedal ,under the dash.

CHECK BRAKE LIGHT SWITCH FUSE.IF FUSE GOOD. POWER GOING TO BRAKE LIGHT SWITCH.REPLACE THE BRAKE LIGHT SWITCH.

WITH A GOOD FUSE TESTER, TEST ALL THE FUSES FUSEBOX UNDER THE HOOD & INSIDE THE VEHICLE. IF THE FUSES ARE ALL GOOD WITH THE TESTER YOU MUST HAVE A BAD BRAKE LIGHT SWITCH OR A BAD TURN SIGNAL SWITCH. THE BRAKE LIGHT CIRCUIT GOES UP THROUGH THE TURN SIGNAL SWITCH & THEN TO THE BRAKE LIGHTS. FIRST OF ALL IS THE BRAKE LIGHT SWITCH GOOD ? THE ORANGE WIRE FEEDS THE BRAKE LIGHT SWITCH, THE WHITE WIRE PUTS POWER TO THE TURN SIGNAL SWITCH, SO THE LIGHTS CAN BE USED AS TURN LIGHTS OR BRAKE LIGHTS. , PUT A TESTER IN THE WHITE WIRE & PRESS ON THE BRAKE PEDAL. IF THE TEST LIGHT LIGHTS UP, BRAKE LIGHT SWITCH IS GOOD, BY THE WAY THE BRAKE LIGHT FUSE MAY BE LABELED" STOP", THE FUSE LABELED" BRAKE" IS FOR THE ABS SYSTEM. TO CHECK THE TURN SIGNAL SWITCH FOR BRAKE LIGHTS, REMOVE THE PLASTIC COVER FROM UNDER THE STEERING WHEEL, PRESS ON THE BRAKE PEDAL, PUT THE TESTER IN THE SMALL YELLOW WIRE, THEN THE SMALL GREEN WIRE. IF THERE IS NO POWER IN EITHER WIRE, THE TURN SIGNAL SWITCH IS BAD.

You checked fuse # F24 in the central junction box. Do you have a volt meter ? check for B+ voltage at the switch ,in an out pushing on the pedal . The orange with yellow stripe wire is power out of the switch .Check out the wiring diagram at http://www.bbbind.com/free_tsb.html do you know how to read a wiring diagram ?

Dear Bearcoop02,
First thing to check is your fuse # 13, 20 amp in the interior fuse box. This is the brake light fuse. If the fuse is ok and all three brake lights are out, pull one of the lamp assemblies out and check for power with the pedal pressed down. Left should be LG/OG and right should be OG/LB. If the power is good,it is probably bulbs. The third light and the brake lights have different grounds.
If there is no power, back up to the stop lamp switch. This switch is located above the pedal,on the pivot.It has two wires. LG/RD should have power all the time and the LG wire when the pedal is applied. If there is no power,the switch is bad.
If there is power,you will need to remove the steering column covers to gain access to the wires into the multifunction switch. Again,with the pedal pressed,the light green wire should have power. This is the input to the switch. If ok,check LG/OG and OG/LB for power with the pedal pressed. If no power,the multifunction switch needs to be replaced.
This should give you the information to trace the circuit back. If you need anything else,don't hesitate to drop me a line.Thanks, Chuck

First I'd check the fuse. Then I'd check the bulbs. Then I'd check the brake switch located under the dash and operated by the brake pedal. Use a test light or multimeter.

That switch should be your Problem. Please Rate My Response! Thanks!

There is a Relay under the Hood in the Fuse Relay Box. Replace this and it should be OK. If not let me know so that we can look elsewhere for the Problem. Please Rate my Solution, I need all the Help that I can Get!