RC Bluetooth Car

#include <SoftwareSerial.h>

#define MotorA_F 4
#define MotorA_B 5
#define MotorB_F 6
#define MotorB_B 7
#define ENA 9
#define ENB 10

#define tx 3
#define rx 2

SoftwareSerial Bluetooth(rx,tx);

char _read;

void setup() {
  pinMode(MotorA_F, OUTPUT);
  pinMode(MotorA_B, OUTPUT);
  pinMode(MotorB_F, OUTPUT);
  pinMode(MotorB_B, OUTPUT);

  pinMode(ENA, OUTPUT);
  pinMode(ENB, OUTPUT);

  Bluetooth.begin(9600);
}

void loop() {
  // Controlling Speed
  analogWrite(ENA, 255);
  analogWrite(ENB, 255);
  if (Bluetooth.available() > 0) {
    _read = Bluetooth.read();

    if (_read == "F") {
      digitalWrite(MotorA_F, HIGH);
      digitalWrite(MotorA_B, LOW);

      digitalWrite(MotorB_F, HIGH);
      digitalWrite(MotorB_B, LOW);
    } else if (_read == "B") {
      digitalWrite(MotorA_F, LOW);
      digitalWrite(MotorA_B, HIGH);

      digitalWrite(MotorB_F, LOW);
      digitalWrite(MotorB_B, HIGH);
    } else if (_read == "L") {
      digitalWrite(MotorA_F, LOW);
      digitalWrite(MotorA_B, HIGH);

      digitalWrite(MotorB_F, HIGH);
      digitalWrite(MotorB_B, LOW);
    } else if (_read == "R") {
      digitalWrite(MotorA_F, HIGH);
      digitalWrite(MotorA_B, LOW);

      digitalWrite(MotorB_F, LOW);
      digitalWrite(MotorB_B, HIGH);
    }
  }

}