How to Program Your JVC Car Stereo Remote: A DIY Guide

Are you looking to enhance your car audio experience by programming your JVC car stereo remote? Whether you’re aiming to integrate steering wheel controls or create a custom remote setup, understanding how to program your JVC car stereo remote can significantly improve convenience and control. This guide will walk you through the process, leveraging Arduino and readily available remote codes to customize your car audio system.

Many modern car stereos, including JVC models, offer versatile control options beyond the standard front panel. Steering wheel controls and infrared (IR) remotes provide added convenience, allowing you to manage your audio system without taking your eyes off the road. Programming these remote functions often involves understanding the underlying communication protocols and, in some cases, utilizing microcontrollers like Arduino for custom solutions.

This article will delve into the specifics of programming a JVC car stereo remote, focusing on utilizing an Arduino platform to interpret steering wheel control inputs and translate them into JVC remote commands. We’ll explore the necessary code, explain how it works, and guide you on adapting it for your own car audio setup.

Understanding the Basics: Steering Wheel Controls and IR Remotes

Car stereos often use digital or analog signals to interface with steering wheel controls. These controls send specific resistance or voltage values to the stereo, which are then interpreted as commands like volume up, volume down, track forward, and so on. Similarly, IR remotes communicate using infrared light pulses that encode specific commands. JVC car stereos, like many others, are designed to recognize a specific set of IR protocols and command codes.

For our project, we’ll focus on using an Arduino to bridge the gap between steering wheel control signals and the JVC car stereo’s remote command system. The Arduino will read the signals from your steering wheel controls and, based on our programming, send out corresponding IR commands that your JVC stereo will understand as if they were coming from a standard JVC remote.

Decoding JVC Remote Commands: Protocol JVC-48

JVC remotes typically use the “JVC-48” protocol for IR communication. This protocol dictates how commands are encoded and transmitted via infrared light. To program our Arduino to mimic a JVC remote, we need to know the specific command codes associated with each function.

Fortunately, a set of JVC remote codes is readily available and often shared within online communities. Here’s a list of common JVC-48 protocol commands, which we can utilize for our Arduino project:

Pwr / ATT: 0xF2A0
DISP: 0xE6B4
Up: 0xE8BA
Down: 0xE9BB
Left / Prev: 0xEFBD
Right / Next: 0xEEBC
Rew: 0xB7E5
FF: 0xB6E4
VOL +: 0xF0A2
VOL-: 0xF1A3
SOURCE: 0xF3A1
Play / Pause: 0xB1E3
Off-hook / PHONE: 0xEDBF
On-hook / Stop: 0xFFAD
SETUP / 1: 0xA1F3
ASPECT / 2: 0xAAF8
RETURN / 3: 0xA0F2
TOP M / 4: 0xA3F1
Up / 5: 0xB8EA
MENU / 6: 0xA2F0
Left / 7: 0xBFED
ENT / 8: 0xBCEE
Right / 9: 0xBEEC
OSD / *: 0xAEFC
Down / 0: 0xB9EB
DUAL / #: 0xFDAF
DIRECT / CLR: 0x99CB

These hexadecimal codes represent the commands for various buttons on a typical JVC remote. We will use these codes in our Arduino program to send the correct signals to the JVC car stereo when a steering wheel button is pressed.

Arduino Code for JVC Car Stereo Remote Programming

The following Arduino code provides a foundation for programming your JVC car stereo remote functionality. This code is designed to read analog inputs from steering wheel controls and translate them into JVC IR commands.

#include <IRremote.h>

#define HOLDTIME 500 // Time after which a button is considered held (milliseconds)
#define DELTA 5       // Error margin for analog signal readings

// Define analog input values for steering wheel buttons
#define MINUS0 18   // Button "-"
#define PLUS0 34    // Button "+"
#define CIRCLE0 58  // Button "0"
#define RIGHT0 91   // Button ">"
#define LEFT0 146   // Button "<"
#define UP0 241     // Button "Up"
#define ALLDOWN 447 // All buttons released

// JVC RM-RK52 remote control commands (and mappings to steering wheel buttons)
#define UP 0xF111    // Steering wheel Up button (mapped to SOURCE)
#define UPH 0xF1B1   // Steering wheel Up button held (mapped to SOUND)
#define LEFT 0xF1C9  // Steering wheel < button (mapped to LEFT)
#define LEFTH 0xF1A9 // Steering wheel < button held (mapped to DOWN)
#define RIGHT 0xF149 // Steering wheel > button (mapped to RIGHT)
#define RIGHTH 0xF129 // Steering wheel > button held (mapped to UP)
#define CIRCLE 0xF171  // Steering wheel O button (mapped to MUTE)
#define CIRCLEH 0xF1B1 // Steering wheel O button held (mapped to SOUND) - Duplicate, should be different if needed
#define PLUS 0xF121   // Steering wheel + button (mapped to VOL +)
#define PLUSH 0xF121  // Steering wheel + button held (mapped to VOL +) - Duplicate, should be different if needed
#define MINUS 0xF1A1  // Steering wheel - button (mapped to VOL -)
#define MINUSH 0xF1A1 // Steering wheel - button held (mapped to VOL -) - Duplicate, should be different if needed

boolean flag = false;      // Flag for button hold repetition
int analog = 0;          // Variable to read analog signal
unsigned long time;      // Variable to store time
IRsend irsend;           // IRsend object from IRremote library

void setup() {
  Serial.begin(9600); // Initialize serial communication for debugging
}

void loop() {
  analog = analogRead(A0); // Read analog signal from pin A0

  if (abs(ALLDOWN - analog) < DELTA) { // Check if all buttons are released
    time = 0;                     // Reset time
    flag = false;                   // Reset flag
  }

  if (abs(ALLDOWN - analog) > DELTA && time == 0) { // Button pressed and not previously pressed
    time = millis(); // Record press time

    do {
      Serial.print("Pushing");
      Serial.print(analogRead(A0));
      Serial.print("by");
      Serial.println(millis() - time);
      delay(50);
    } while (abs(ALLDOWN - analogRead(A0)) > DELTA && millis() - time <= HOLDTIME); // Wait for button release or hold time

    if (millis() < time + HOLDTIME && flag == false) { // Single button press
      if (abs(analog - UP0) < DELTA) {        // Up button
        irsend.sendJVC(UP, 16);              // Send SOURCE command
        Serial.print("com1");
        Serial.println(UP, HEX);
      }
      if (abs(analog - LEFT0) < DELTA) {      // Left button
        irsend.sendJVC(LEFT, 16);            // Send LEFT command
        Serial.print("com1");
        Serial.println(LEFT, HEX);
      }
      if (abs(analog - RIGHT0) < DELTA) {     // Right button
        irsend.sendJVC(RIGHT, 16);           // Send RIGHT command
        Serial.print("com1");
        Serial.println(RIGHT, HEX);
      }
      if (abs(analog - CIRCLE0) < DELTA) {    // Circle button
        irsend.sendJVC(CIRCLE, 16);          // Send MUTE command
        Serial.print("com1");
        Serial.println(CIRCLE, HEX);
      }
      if (abs(analog - PLUS0) < DELTA) {      // Plus button
        irsend.sendJVC(PLUS, 16);             // Send VOL + command
        Serial.print("com1");
        Serial.println(PLUS, HEX);
      }
      if (abs(analog - MINUS0) < DELTA) {     // Minus button
        irsend.sendJVC(MINUS, 16);            // Send VOL - command
        Serial.print("com1");
        Serial.println(MINUS, HEX);
      }
    } else if (millis() >= time + HOLDTIME) { // Button held down
      if (abs(analog - UP0) < DELTA) {        // Up button held
        irsend.sendJVC(UPH, 16);             // Send SOUND command
        Serial.print("com2");
        Serial.println(UPH, HEX);
      }
      if (abs(analog - LEFT0) < DELTA) {      // Left button held
        irsend.sendJVC(LEFTH, 16);            // Send DOWN command
        Serial.print("com2");
        Serial.println(LEFTH, HEX);
      }
      if (abs(analog - RIGHT0) < DELTA) {     // Right button held
        irsend.sendJVC(RIGHTH, 16);           // Send UP command
        Serial.print("com2");
        Serial.println(RIGHTH, HEX);
      }
      if (abs(analog - CIRCLE0) < DELTA) {    // Circle button held
        irsend.sendJVC(CIRCLEH, 16);          // Send SOUND command - Duplicate, consider changing
        Serial.print("com2");
        Serial.println(CIRCLEH, HEX);
      }
      if (abs(analog - PLUS0) < DELTA) {      // Plus button held
        irsend.sendJVC(PLUSH, 16);            // Send VOL + command - Duplicate, consider changing
        Serial.print("com2");
        Serial.println(PLUSH, HEX);
      }
      if (abs(analog - MINUS0) < DELTA) {     // Minus button held
        irsend.sendJVC(MINUSH, 16);           // Send VOL - command - Duplicate, consider changing
        Serial.print("com2");
        Serial.println(MINUSH, HEX);
      }
      flag = true; // Set flag to indicate button hold was processed
    }
  }
  delay(100); // Delay for stability
}

Code Explanation: Breaking It Down

#include <IRremote.h>: This line includes the necessary IRremote library, which simplifies sending IR signals with Arduino. You’ll need to install this library in your Arduino IDE if you haven’t already.
#define Statements: These lines define constants used throughout the code.
- HOLDTIME: Sets the duration (in milliseconds) after which a button press is considered a “hold”. This differentiates between a short press and a long press.
- DELTA: Defines a small error margin for analog readings. This is important because analog readings can fluctuate slightly.
- MINUS0, PLUS0, CIRCLE0, RIGHT0, LEFT0, UP0, ALLDOWN: These define the expected analogRead values from pin A0 when each steering wheel button is pressed, and when no button is pressed (ALLDOWN). You will likely need to adjust these values based on your specific car and steering wheel control interface. You can determine these values by monitoring the analog readings in the serial monitor as you press each button.
- UP, UPH, LEFT, LEFTH, etc.: These define the JVC remote command codes (in hexadecimal format) that will be sent when the corresponding steering wheel button is pressed or held. These are mapped to specific JVC remote functions as commented in the code (e.g., UP is mapped to SOURCE). You can customize these mappings as desired.
boolean flag = false;: This variable is used to track whether a button hold action has been processed to prevent repeated actions while a button is held.
int analog = 0;: This variable stores the current analog reading from pin A0.
unsigned long time;: This variable stores the timestamp of when a button was initially pressed.
IRsend irsend;: This creates an IRsend object, which we will use to send the IR signals.
void setup() { ... }: The setup() function runs once at the beginning.
- Serial.begin(9600);: Initializes serial communication at 9600 bits per second. This is used for debugging and monitoring the analog readings.
void loop() { ... }: The loop() function runs continuously.
- analog = analogRead(A0);: Reads the analog voltage on pin A0 and stores it in the analog variable.
- Button Release Detection: if (abs(ALLDOWN - analog) < DELTA) { ... }: Checks if the current analog reading is close to the ALLDOWN value (meaning no button is pressed). If so, it resets the time and flag variables.
- Button Press Detection: if (abs(ALLDOWN - analog) > DELTA && time == 0) { ... }: Checks if an analog reading is significantly different from ALLDOWN and if time is 0 (meaning a new button press). If so, it records the current time using millis().
- Hold Time Check: The do...while loop waits for either the button to be released or for the HOLDTIME to elapse.
- Single Press Action: if (millis() < time + HOLDTIME && flag == false) { ... }: If the button is released before HOLDTIME, it’s considered a single press. Inside this block, a series of if statements check which button was pressed based on the analog reading (abs(analog - UP0) < DELTA, etc.) and sends the corresponding JVC IR command using irsend.sendJVC(command, 16);.
- Hold Action: else if (millis() >= time + HOLDTIME) { ... }: If HOLDTIME elapses, it’s considered a button hold. Similar to the single press section, if statements check which button is held and send the corresponding “held” JVC IR command (irsend.sendJVC(UPH, 16);, etc.).
- flag = true;: Sets the flag to indicate that a hold action has been processed.
- delay(100);: A small delay to stabilize readings and prevent the Arduino from overwhelming the serial port and IR transmitter.

Adapting the Code for Your Setup

Identify Analog Values for Your Steering Wheel Controls:
- Connect your steering wheel control wires to the analog input pin A0 of your Arduino.
- Upload the code to your Arduino.
- Open the Serial Monitor in the Arduino IDE (Tools > Serial Monitor).
- Observe the analog readings when no button is pressed and when each steering wheel button is pressed. Note down these values.
- Update the #define values MINUS0, PLUS0, CIRCLE0, RIGHT0, LEFT0, UP0, and ALLDOWN in the code to match the values you observed.
Verify JVC Remote Codes:
- The provided JVC-48 codes are generally standard, but it’s always good to verify them if possible. You might find resources online that list JVC remote codes for your specific stereo model.
- If you have an IR receiver module, you can use an Arduino IR receiver sketch to capture the IR codes from your original JVC remote to confirm the codes.
Customize Button Mappings:
- The code currently maps steering wheel buttons to specific JVC remote functions (e.g., Up button to SOURCE).
- Modify the #define UP 0xF111, #define LEFT 0xF1C9, etc., lines to change these mappings to your desired functions. Refer to the JVC remote command list provided earlier to select the functions you want to assign to each steering wheel button.
- Pay attention to the “held” button commands (UPH, LEFTH, etc.). These are triggered when you hold a button down. You can map these to different functions than the single press commands if you wish.
Wiring:
- Connect the appropriate wire from your car’s steering wheel control interface to the Arduino’s analog input pin A0. You may need to consult your car’s wiring diagram and the documentation for your aftermarket stereo adapter (if you are using one).
- Connect an IR LED to a digital output pin on your Arduino (e.g., pin 3, as often used by the IRremote library) and a ground pin. Make sure to use a current-limiting resistor in series with the IR LED. Position the IR LED so it can transmit signals to your JVC car stereo’s IR receiver.
Testing and Refinement:
- After making your code modifications and wiring connections, upload the updated code to your Arduino.
- Test each steering wheel button and verify that it controls the corresponding function on your JVC car stereo as you intended.
- You may need to fine-tune the #define DELTA value if you are experiencing issues with button press detection. You might also need to adjust the HOLDTIME value to your preference.

Conclusion

Programming your JVC car stereo remote using Arduino opens up a world of customization possibilities, from integrating seamless steering wheel controls to creating entirely bespoke remote solutions. By understanding the JVC-48 protocol, utilizing the provided Arduino code as a starting point, and carefully adapting it to your specific car and JVC stereo model, you can significantly enhance your in-car audio experience and enjoy a more convenient and personalized control system. Remember to always prioritize safety and consult relevant documentation for your car and stereo system during installation and setup.