Servo works but no Throttle

We run into reports of calibration issues, Programming issues, or Steering Works, but Throttle does not work.
Often nothing in/with the ESC actually causes the problem. This is fairly common and ties to reports of a Speed Control that "Blink" and won't respond, or get "stuck" in the process, won't start the process or seem to complete the process, but do not work after.

If the ESC lights up and functions, it's about 99.99% the ESC is okay and should calibrate with a correctly working "Throttle Channel".
We understand your radio functions, but checking the throttle channel is okay is the next step.

A radio system can look to work, but have a dead throttle channel, or a throttle channel that has abnormal outputs.

- Please see the testing below, and reply to this email with a confirmation as to the outcome of your test.

When you connect the Servo, into the Throttle Channel, and Operate the Throttle on the Radio, "Does the servo Move"?

This test is assuming that you turn on the vehicle now and can operate the Steering, and the Servo responds correctly.
How to confirm that RX throttle is operational.
- Plug a servo into the Throttle Channel.
- Plug the ESC into the "Battery Slot" or the "Bind Slot" on the RX.

Turn it on, and move the throttle on the radio.
- If the servo does not move, you have discovered the problem.

The 'Servo test' in the throttle, lets you "see" how far the servo moves when you move the Throttle and Reverse.
- The idea is that it should move the same amount both directions. Often, it does not. This can make the ESC get stuck or not calibrate. The radios settings need to be reviewed so that the Brake/Reverse side is the same as the throttle.

In many problem situations, the throttle does not work at all, or the neutral is way off, or the brake side does not operate correctly. This test helps confirm that your throttle/neutral/Brake/Rev on your radio system is working or not working. If it is not working, the ESC will also not work.

It is important to check your radios "Frame Rate" settings. Some "racing" radio systems, have a frame rate, or "Modes" that operate faster than normal for usage with digital servos. This mode, or "Super fast frame rate" often will make the ESC not able to calibrate, or work strange after calibration. Similar topics happen with various "Brake" and "Throttle" modes from radios. It is always worth checking these specialized settings if you run into any calibration problems.

We receive cases of ESC's that "Do not work", or "Will not calibrate", or, "Will not start calibration" or "gets stuck" in calibration, "works but not correctly", however upon testing by our tech's, they work completely fine. They calibrate and function as they should, beyond units with the physical damage of some sort.

Additionally, we have found replacing these ESCs, "Just in case" yields no fix to the problem.
Now the builders have now spent time and energy to find the problem was not at all related to the ESC. This is of course extremely frustrating and many point to "all" of the ESC's being bad. This is not the case. Never hurts to clarify what you've done to confirm the rest of the items in your build are working correctly, and help pinpoint topics to check specifically.

Finally, some high-end racing radios, have a very fast "Frame rate" settings for their channels. Often these do not allow the ESC to see the signals from the radio. If your radio controller, has ultra-fast frame rate settings, putting those on "normal" should get things working again.

Here is a video doing the Basic Servo Test:
https://www.youtube.com/watch?v=NWCgbxWIp24

Here is a video doing the calibration.
https://www.youtube.com/watch?v=RRYwr14FwjE