RFID Again!

Just a small number of tags will be issued 5 at max. I think using part of your code will work

#include <SoftwareSerial.h>
#define rxPin 2
#define txPin 3

//create a Serial object RFID
SoftwareSerial RFID = SoftwareSerial(rxPin, txPin);
char code[20];

int val = 0;
int bytesread = 0;

char Red[]    = "3900A502C35D";     // Tag ID.
char Blue[]   = "39009F2DAD26";    // Tag ID.
char Yellow[] = "39005082A843";    // Tag ID.
char Card1[]  = "140029A6079C";   //  etc..
char Card2[]  = "14002943BFC1";  //   etc..

int ledCnt = 5;
int LED[] = {13, 11, 9, 7, 5};

void setup()
{
  Serial.begin(9600); //open serial hardware
  RFID.begin(9600); //open serial software

  pinMode(rxPin, INPUT); //set pin on arduino for receiving RFID data
  pinMode(txPin, OUTPUT); //this is not important

  for(int i=0; i<ledCnt; i++)
  {
    pinMode(LED[i], OUTPUT);
  }
}

void loop()
{
  val = 0;
  bytesread = 0;

  while(bytesread < 12)
  {
    // read 12 digit code
    val = RFID.read();
    if(val == 3)
    { // if header or stop bytes before the 10 digit reading
      break; // stop reading
    }

    if(val != 2)
    {
      code[bytesread] = val; // add the digit
      bytesread++; // ready to read next digit
      code[bytesread] = '\0'; // add the NULL
    }
  }

  if(bytesread >= 12)
  { // if 12 digit read is complete
    Serial.print("Tag: [");
    for(int i=0; i<bytesread; i++)
    {
      Serial.print(code[i]);
    }
    Serial.println("]"); //print the whole 13 bytes
    int tag = FindValidTag(code);
    Serial.print("Tag number: ");
    Serial.println(tag);

    for(int i=0; i<ledCnt; i++)
      digitalWrite(LED[i], LOW);
    if(tag > 0 && tag <= ledCnt)
      digitalWrite(LED[tag-1], HIGH);
  }
}

int FindValidTag(char *code)
{
  if(strcmp(code, Red) == 0)
    return 1;
  else if(strcmp(code, Blue) == 0)
    return 2;
  else if(strcmp(code, Yellow) == 0)
    return 3;
  else if(strcmp(code, Card1) == 0)
    return 4;
  else if(strcmp(code, Card2) == 0)
    return 5;
  else
    return 0;
}

However how to modify this to include the keypad, LCD, and triggering a relay instead of LED's is what I'm working on now.

How can I eliminate the LED's and just pull one pin high on a matched read regardless of the number? I also need to be able to manually enter a code and pull a pin high to energize a relay module I have to power the electric door latch.