Jumping doesn't work, and I don't know why.

This jump function does not work, and I don’t know why. Doesn’t do anything when I hit space.
Can Anyone Debug it?

using UnityEngine;

[RequireComponent(typeof(playerMotor))]
public class playerController : MonoBehaviour {

[SerializeField]
private float speed = 5f;

[SerializeField]
private float lookSpeed = 3f;

[SerializeField]
public Vector3 jump = Vector3.up;
public float jumpForce = 3.0f;

private Rigidbody rb;

private playerMotor motor;

void Start()
{
    rb = GetComponent<Rigidbody>();
    motor = GetComponent<playerMotor>();

}

void Update()
{
    float _xMov = Input.GetAxisRaw("Horizontal");
    float _zMov = Input.GetAxisRaw("Vertical");

    Vector3 _movHorizontal = transform.right * _xMov;
    Vector3 _movVertical = transform.forward * _zMov;

    Vector3 _velocity = (_movHorizontal + _movVertical).normalized * speed;

    motor.Move(_velocity);

    float _yRot = Input.GetAxisRaw("Mouse X");

    Vector3 _rotation = new Vector3(0f, _yRot, 0f) * lookSpeed;

    motor.Rotate(_rotation);

    float _xRot = Input.GetAxisRaw("Mouse Y");

    float _camRotationX = _xRot * lookSpeed;

    motor.RotateCamera(_camRotationX);

    if(Input.GetKeyDown(KeyCode.Space))
    {

        rb.AddForce(jump * jumpForce, ForceMode.Impulse);

    }

}

}

I think that your jumpforce might be just too small. 3.0f is really little. Try bumping it up to something like 300f.