There are several things it could be, but the most obvious and common is a bad battery. Most people incorrectly diagnose this as the alternator, however, it is in fact a bad battery. The battery is not holding a charge and is constantly placing a full drain on the alternator produing your flickering/pulsing. Check the voltage on the battery with the engine off immediately after running the engine for at least 15min. Wait a few hours (overnight even better) and check the voltage again. Anything more than a tenth of a volt drop or even really hundredths or so and you have a failing battery. For ex. right after running if the battery reads 12.5V and then after say 8-12+ hours if the battery reads 11.9V you definitely have a failing battery. If it does not seem to be a bad battery, repost and we'll go from there on less likely causes.
No, you need to use the grill from a 99-00 cougar if you want to use their headlights. I think there are some issues with the lights not clearing the bumper cover on too. Read through some of the headlight threads on newcougar.org, that should be able to better answer your questions.
You may have a pull on your batt, or a surge.
Sounds like you need a new battery.
Yes, but you will have to do some trimming inside the engine bay as the '02 lights go farther back into the vehicle than the originals did. More info at http://newcougar.org/
why do my lights flicker and interior lights flicker
I had this problem and it was a bad alternator.
If the lights flicker when the vehicle is running, the alternator is on it's way out.
Those aren't headlights, they're considered running lights or parking lights. I believe that mercury calls this a Light Bar.
by licking stuff
Flickering headlights on a 2005 Silverado may be caused by faulty relays or electrical wiring. The fuses and lights may also be going out.
Your lights may flicker because they power is really low. It is very common for them to flicker when there is a storm out.
Turn on headlights/parking lights and adjust dimmer control
try fuse 24
If your headlights work, but your tail lights don't, your bulbs could be blown. It is possible that you have a shortage in your car.
where you turn on the headlights ... push the button
You can view the 1999 Mercury Cougar owners manual online at : www . motorcraft service . com ( no spaces ) Click on Owner Guides
You can view the 2001 Mercury Cougar owners manual online at : www . motorcraft service . com ( no spaces ) Click on Owner Guides
On a 1999 GEO Tracker, a bad fuse can cause the headlights and dash lights to blink. A bad voltage regulator or alternator can also cause lights to blink and flicker.
remove dash replace bulb(instrument cluster)
Pull the headlight switch towards you.
Your brake light switch under your pedal is brobaly stuck
check the switch at the break peddle
Well when you are driving the alternator is at a constant speed then when you slow down the alternator sort of skips a beat causing the lights to dim!
Have your alternator tested. They will sometimes do that when they are putting out low outputs at low rpm.
You can view the 1999 Mercury Cougar Owner Guide online at : motorcraft service . com ( no spaces ) Click on Owner Guides The Owner Guide has pictures and meanings