Our '97 RL came with black, grey, and red keys. I know what the black and grey are for. Can anyone tell me what the red key is for?

 

The red key is the "learning" key. It is used by the Acura/Honda dealers to code replacement keys to your cars immobilizer system. "DO NOT" attempt to start your car's engine with the red key as it may cause a malfunction in the immobilizer system and make your master and valet keys unusable (as per the owners manual.)

 

The red key is evil. Don't ever use it. Lock it in a safe. Put a note on it.

 

Ok, get the red key and try to start the car with it. Got it.