Servo not working anymore?

Unfortunately you don't say which servo is no longer moving. Is it the steering servo, or the throttle and brake servo, or does the model have other servos?

• If all the servos in your car have failed, you need to look for the problem in the receiver battery, the receiver, or the remote control. Is it just one servo that's not working?
• First, check whether the part the servo is supposed to operate is jammed somewhere. Can you move the servo by hand when it's turned off? In RC cars, small stones or similar objects often get stuck in moving parts.
• Especially with steering servos in RC cars, the servo gears break very easily. Remove the servo, clean its outside and unscrew the four screws that hold the servo in place. Then carefully lift off the cover so that no gears fall out. You should be able to see if any gears are broken. Replacement gears are available for many servos. However, the servos in RTR cars are often very cheap. Especially with the steering servo, you should opt for a high-quality digital servo with multiple ball bearings and a metal gear. You can find a suitable one at a model shop. I don't know whether the Carbon Fighter uses a standard size or quarter scale steering servo. You'll have to check that, or clarify it with your local dealer or over the phone.
• If one servo works and the other doesn't, you can also swap the throttle and steering servo cables on the receiver and see if the same thing still doesn't work. (Don't forget to swap it back.) If the same servo still doesn't work, then it's the servo or something related to it. If the other one doesn't work, it's more likely the remote control or the receiver.