I just installed some new LEDs in the outside taillights in my 97 Accord. They both work, but the warning light is still on and the cruise control won't work. How do I get the warning light to go away? It's my first LED installation and I don't know what is wrong

 

Are those the lamps with the brake lights too? If so, the LEDs have to have resistors to give the expected current for the brake-lamp-failure circuits? Some LEDs might not have those resistors.

 

They are the ones with the brake lights. I heard about the resistors, but then I was confronted with the fact there are different levels of resistors, and I don't know which to pick. There were 3, 6, and 9 ohm resistors, and I don't know which to pick for my car.

 

You said "but the warning light is still on" which I take to mean that it was on prior to the install, and thus I have to say have you checked the brake fluid reservoir level or the brake fluid switch may be faulty or dirty, although the later is less common. As far as the cruise control not working that sounds like a separate issue.

 

It's not an issue with the brakes, it is the brake light. The warning light that tells you a brake light is out is still on. I lost a brake light so that came on, then after I replaced them both with LEDs, that light was still on signaling one or both brake lights were out, yet they work perfectly fine

 

Low fluid in the master cylinder will cause the light to stay on as indicated. If it has something to do with an aftermarket resistor and all other electrical checks out fine then I am out of the conversation as I don't like to nor will deal with aftermarket electrical in the shop. It is not worth my time. I hope that someone else here will be able to help you. Good luck.

 

Low brake fluid will set off the brake warning lamp, the same lamp that comes on with the parking brake.
That's a different lamp than the brake-light bulb-failure warning lamp.

I don't know what value of resistor, I suppose you want a similar resistance that the stock incandescent bulb would have.