Autonomous Control of RC Car Using Arduino





Introduction: Autonomous Control of RC Car Using Arduino

This instructable shows how to modify an inexpensive RC car so it can be controlled by an on-board microcontroller.  You can program the controller to make the car do any number of driving patterns and stunts.  Once you have the car being controlled from the on-board controller, you can add sensors for light and sound and make the car do things like line following.

Step 1: Gather Materials and Tools

I used the following materials:
-RC Car - el cheapo from Walmart.  It cost $6 at my local Walmart.
-Arduino - I used the Duemilanove purchased from Sparkfun, (
-4 1000 Ohm 1/8 Watt resistors (color code BRN/BLK/RED). The value of the resistors is not critical.  Anything within 50% should work.
- 1/16th inch heatshrink tubing to insulate the resistors after they're installed
- 22 AWG solid  wire.  You'll need five wires, 6 to 8 inches long. I used Black for the Ground and White for the 4 control wires.
- a small amount of solder
 - 2 rubber bands
- 9V battery clip that plugs into the Arduino, also available from Sparkfun

Tools you'll need are:
- small (not tiny) Phillips screwdriver
- wire stripper
- soldering iron
- "third hand" to hold resistors while soldering wires to them
- small tip diagonal wire cutters
- desoldering tool or braid
- tweezers or small needle-nose pliers

Step 2: Disassemble the Car

For this step, you will take the car apart.  First, clip off the antenna using a strong pair of cutters.  Then, remove the four screws that hold the body on the chassis and separate the body from the chassis.   Next, remove the two screws that hold the internal electronics cover. Discard this cover.

Step 3: Remove the Antenna

Remove the screw holding the antenna.  Cut the antenna wire near the printed circuit board being careful to only cut the black antenna wire.  Discard the antenna and antenna wire. 

Step 4: Hack Into the Car's Electronics

Unscrew the single screw holding the printed circuit board (PCB) to the chassis.  Carefully turn the PCB over and screw it back down temporarily.  Now, using small tip wire cutters, carefully clip each lead on the controller chip.  Be sure not to cut any other leads or wire on the PCB. Remove and discard the controller chip.

Step 5: Connect the Wires

Flip the PCB back over.  Using a solder sucker or solder braid, unsolder and clean out the holes for pins 2,6,7,10 & 11.  Be careful not to use too much heat to avoid damaging the PCB.  Prepare four resistor/wire assemblies as follows: Solder solid 22 gauge white wire to a 1K Ohm resistor.  Make a total of four of these resistor/wire assemblies.
Insert and solder the resistor leads (the ones not connected to the wire) into the holes for pins 6,7,10 & 11.  After soldering, slip a piece of shrink tubing over the wire all the way down to the PCB.  Shrink the tubing with a match, lighter or tubing shrinker.

Install and solder a solid black wire into the hole for pin 2.

Mark the white wires with stripes so you'll know which wires control the different functions.
1 stripe - Left signal - pin7;
2 stripes - Right signal - pin 6;
3 stripes - Reverse signal - pin 10;
4 stripes - Forward signal - pin 11;

Step 6: Route the Wires and Reassemble the Car

Drill a 3/8" hole in the rear of the car body for a place where the wires will come outside the car.  Place the body on top of the chassis while threading the wires through the hole in the trunk.  Screw the body and chassis together using the 4 screws previously removed.

Step 7: Attach the Arduino

Using rubberbands, attach the Arduino to the roof of the car.  Strip the ends of the wires and plug them in to the Arduino pins according to how the program works.  Also attach a 9V battery holder and plug it into the Arduino.

Next connect the black wire into the GND pin on the Arduino.  Then connect the white wires to the Arduino as determined by your program.

These statements in the Arduino program determine which pins the white wires plug into:
int forward = 12; // forward pin
int reverse = 11; // reverse pin
int left = 10; // left pin
int right = 9; // right pin

Step 8: The FUN! Part

Attached to this Instructable is the Arduino sketch used to make a car go into a continuous figure 8 and a video showing a car doing various tricks.

Some things to remember:
1.  Put batteries in the car.
2.  Make sure the car is turned OFF.
3.  Connect the 9V battery to the Arduino.
4.  Verify and Upload the cartest sketch from your computer into the Arduino.
5.  Disconnect the programming cable.
6.  Turn the car on - it should start running immediately.

If you're new to the Arduino, you can find all the information you need and the programming software at

Have Fun!!!



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Hello, I am new to all of this, and my first project is this since it is suppose to be easy. Well first problem that I got was taking apart my vehicule. My board has three chips instead of one... I am already stomped. Looked around and it seems that all other cars have only one.

Writing the number of the chips... and wondering if still possible to plug ardwino?




Thanks in advance, really want to do this....

1 reply

It is posible to remove board completly and connect motors to arduino DC driver for motors. But for instructrions You will have to try with Googleing. It's not dificult.

Can You please tell me the brand and model of your car because I have that exact electronic but could not find the apropriate Remote Controller to drive it.

Instead of modifying the control board of the R/C car, it's simpler to replace the whole board with an L298N Dual H-Bridge Motor Controller. The board in the latest R/C car I bought is to small to modify.

5 replies

the L298N has a 3V drop between VCC and your motors... it works great but only on high voltage applications.

You can make your own H-Bridge too but have to use higher end transistors to avoid the same voltage drop... 2n390x won't work very well. This becomes price prohibitive.

For most cars the original poster's idea works well and is super easy, and you end up using the cars built-in H-Bridge which is usually more efficient. Most cheap RC cars use the same control chip so the wiring is the same (even on different brands). The poster in this case identified the wiring on this model RC car, but if you look closely at the actual board you will find the same chip (and pins) on most other cars as well. You just have to verify which wires trigger forward/backward/left/right and use the Arduino to flip those positive or negative to activate each circuit. Pretty easy once you do it once or twice.

Thanks your post is very instructional... and you might solve my problem, I have three chip in my car...?

I will put picture of my board... very soon.

The difficulty is soldering wires to the tiny board on the cheap R/C car I bought from Target. A 5 pack AA battery pack that came with the car provided plenty of power to drive the R/C car motors via the L298N. We won the race with this design. These R/C cars are so fast compare to the standard Aduino car kit.

Hello i have batman monsternam rc truck but i dont have remote c how can i program with arduino?

Also really happy to try new things, never programmed before nor used arduino, but since your comment says a summer camp person could do this... ha! well thanks for giving me the motivation.


New to everything, and well my radio controlled car has 3 chips... do I remove all of them? Thanks

The instructions were very helpful. I am from a computer science background. The RC Car uses RX-2B receiver. I followed the steps given in the PDF, now the RC car is not functioning at all, with or without Arduino. Let me know if any one can help me.

2 replies

I'm having the exact same problem as you right now. Did you solve the problem yet? Please help me!

If you are agree with work to gether by online then we make best projects on robot ,i study electrical engineering and you are best knowledge in computer so if we work together then we make programebal robot my contact no on whtsup is 8128889855

With best complement akshay dalsaniya

Hey i need some help; i have an old same type of rc car which has a broken circuitary(20 yrs old car) it's motors still work and i'm facing trouble managing them. it has enough space to fit an arduino with 5V 2amp powerbank. I have individually tested the motor with various amps (0.5-2). Reverse polarity will make motors run forward or backward. the thing is using a pwm pin of an arduino limits to 80mA i guess. how can one achieve reverse polarity with such motor with only two leads? though of using TIPs but donno anything much about electronics...(basically a computer science graduate).. please send suggestions on how it can be made to work.. i have 2 months time as i need it working for my uncle's birthday as he is the one who gifted it.. :)

What happens if your my rc car doesnt have an controller chip?


Hey, can I ask for a schematic diagram for this? Just email me via

Great work btw!

1 reply

Would you mind sending it to me too please?

very interesting! if you took the arduino chip out of the programming board or got a smaller version you could even fit it all inside the car! 5*s