The idea of starting the engine with a start / stop button is not new, at first they were used on sports cars, now on many modern cars they are already being put on the conveyor. There are many Chinese startup options with a button, immobilizers, etc.
On my VW Tiguan there is such a system, but on my second car, the Opel Vectra In 96g. I didn’t think of putting a start / stop button, in general I thought it was a show off. There is an alarm with Pandora 3700 autostart, and you can start the car with a key. But there was a breakdown of the ignition cylinder. Once already changed it. Naturally, to make it cheaper, I did not buy and change the larvae on the door and trunk locks. This caused inconvenience, 2 keys in a bunch, etc. And maybe I would change the ignition switch or the larva again, but here the button from the Chinese “set” Start / Stop turned up successfully for an inexpensive price. Now I decided to redo it.
Really like the Microchip PIC12F629 microcontrollers, small ones, easy to program. Do not freeze in our frosts (verified). Therefore, I do not implement complex logic on them. Here is what was born:
On my VW Tiguan there is such a system, but on my second car, the Opel Vectra In 96g. I didn’t think of putting a start / stop button, in general I thought it was a show off. There is an alarm with Pandora 3700 autostart, and you can start the car with a key. But there was a breakdown of the ignition cylinder. Once already changed it. Naturally, to make it cheaper, I did not buy and change the larvae on the door and trunk locks. This caused inconvenience, 2 keys in a bunch, etc. And maybe I would change the ignition switch or the larva again, but here the button from the Chinese “set” Start / Stop turned up successfully for an inexpensive price. Now I decided to redo it.
Really like the Microchip PIC12F629 microcontrollers, small ones, easy to program. Do not freeze in our frosts (verified). Therefore, I do not implement complex logic on them. Here is what was born:
Circuit diagram:
Description of the circuit: when disarming the alarm, transistor Q4 supplies power to the circuit. The start / stop button S1 is highlighted by blue LEDs, they also light up.
Here's one from my Chinese kit:
LEDs, unfortunately, burned weakly at 5 volts, but burn brightly at 12 volts of power. Therefore, the connection diagram of the button was changed and changed the resistance of R2 and R3:
Transistor Q1 turns on the ignition relay and the immobilizer bypass relay (if needed). You can also connect a relay if the ignition has 2 outputs (Ignition1 and Ignition2). The drain current of the transistor A03400 to 4.4A, withstand. Q2 includes a starter relay, Q3 - ACC relay.
You can start the engine in several ways:
1. Press the start / stop button. The ignition will turn on, after 5 seconds the ACC will turn on, no power will be supplied to the starter. Then we press the brake, if the button is not released, the ACC will turn off and the starter will turn on. As soon as the engine starts, the starter will automatically turn off and after 5 seconds the ACC will turn on. You can release the button. OR, if the button has been released, then press and hold it again until the engine starts.
2. Press the brake pedal, then the start / stop button and do not release. The ignition will turn on, after 2 seconds the starter will turn on and, if the engine starts, it will automatically turn off. ACC will turn on after 5 seconds.
The starter cut-off is programmed for 8 seconds in case the engine does not start. When I measured the compression in the cylinders, this time was enough.
To prematurely interrupt the starter, you can release the button or brake pedal.
3. If for some reason, for example, the battery is dead, but the ignition turns on, or there is a problem with the starter, we decided to start it with the pusher. The unit registers the engine started and the starter will not turn on when the brake and the start / stop button are pressed. Wow, it seems I described it correctly.
You can add an algorithm so that the engine starts automatically from a single press of a button with the brake pressed. On some cars I saw this algorithm. But it seemed to me uncomfortable.
The engine turns off by briefly pressing the start / stop button.
Of course, if the car is with a manual gearbox, it is better to put an additional switch (frog) on the clutch pedal and connect to it instead of the brake. I didn’t put it and it doesn’t cause me problems personally. In the summer I start the engine without pressing the clutch pedal. In winter, I press both the clutch and the brake at the same time, the engine starts without pre-gasing.
1. Press the start / stop button. The ignition will turn on, after 5 seconds the ACC will turn on, no power will be supplied to the starter. Then we press the brake, if the button is not released, the ACC will turn off and the starter will turn on. As soon as the engine starts, the starter will automatically turn off and after 5 seconds the ACC will turn on. You can release the button. OR, if the button has been released, then press and hold it again until the engine starts.
2. Press the brake pedal, then the start / stop button and do not release. The ignition will turn on, after 2 seconds the starter will turn on and, if the engine starts, it will automatically turn off. ACC will turn on after 5 seconds.
The starter cut-off is programmed for 8 seconds in case the engine does not start. When I measured the compression in the cylinders, this time was enough.
To prematurely interrupt the starter, you can release the button or brake pedal.
3. If for some reason, for example, the battery is dead, but the ignition turns on, or there is a problem with the starter, we decided to start it with the pusher. The unit registers the engine started and the starter will not turn on when the brake and the start / stop button are pressed. Wow, it seems I described it correctly.
You can add an algorithm so that the engine starts automatically from a single press of a button with the brake pressed. On some cars I saw this algorithm. But it seemed to me uncomfortable.
The engine turns off by briefly pressing the start / stop button.
Of course, if the car is with a manual gearbox, it is better to put an additional switch (frog) on the clutch pedal and connect to it instead of the brake. I didn’t put it and it doesn’t cause me problems personally. In the summer I start the engine without pressing the clutch pedal. In winter, I press both the clutch and the brake at the same time, the engine starts without pre-gasing.
Details:
1. PIC12F629 -1; (Chip-Dip price - 97rub, on Aliexpress bought for 37 rubles.);
2. 78L05 -1; (5V voltage stabilizer);
3. All resistors 0.125W, ratings on the circuit;
4. Diode D1 (any low-power);
5. Diodes D2, D3 - 1N1404; (more powerful, 1A);
6. Ceramic and electrolytic capacitors are indicated in the diagram;
7. Transistors Q1, Q2, Q3 - AO3400 field N-type; (price on Aliexpress 96 rub / 100pcs.);
8. Transistors Q4 - AO3401 field P-type; (price on Aliexpress 96 rub / 100pcs.);
9. Automotive relays; 12V, 40A. I used the Pandora RMD-5 relay startup module;
10. Any immobilizer bypasser, for example Pandora DI-02;
11. Start / stop button from the Chinese set or any suitable without fixing;
12. Mounting plate for soldering;
13. Fuse with holder for 7.5A.
The microcontroller programmed using the PicKit2 programmer, hex file
The device has a small number of elements and is easy to manufacture. We put the soldered board in a suitable box, in my box from the alarm.
Mounting the device on a car is no different from installing an alarm with auto start. The scheme is universal.
The ignition switch must be unlocked and left in the unlocked state. The Chinese in their instructions write that you need to saw off the key and leave it in the larva:
It was easier for me, because the larva was already broken and the key was calmly pulled out of the lock.
About the fact that now there is no steering column lock I’m not worried. With a certain dexterity, the standard locking bolt can also be broken. And I additionally have an immobilizer.
Next, disconnect the connector from the contact group of the ignition switch and connect the power wires from the relay to the wires according to the diagram. I connected to the previously installed Pandora RMD-5 power launcher.
About the fact that now there is no steering column lock I’m not worried. With a certain dexterity, the standard locking bolt can also be broken. And I additionally have an immobilizer.
Next, disconnect the connector from the contact group of the ignition switch and connect the power wires from the relay to the wires according to the diagram. I connected to the previously installed Pandora RMD-5 power launcher.
2 relays R1, R3 - used for ignition. R4, R5 - ACC, R2 - starter.
Be sure to consider the current load of the relay. On some cars (especially older ones), the ignition lock contact group on terminal 15 is designed for a current of more than 40A, so the relay needs to be set more powerful, for example, a starter from the Gazelle at 70A. The usual 40 amp car relays in this case will fail over time.
Connection diagrams on the example of the car Opel Vectra B 1996:
I only had a problem installing the button in place. The hole in the casing for the ignition cylinder was larger than the button itself. I got out of the situation with the help of a black tin lid from some kind of jam. It fit well in size.
There are 4 mounting holes and one for the cable in the cover.
It should be like this.
The metal plate on the button is held on by 4 screws, with the help of which the Chinese recommend mounting the button on the ignition switch. She used it as a template for the place of the mounting holes on the cover.
Just pierced with an awl.
Not very accurately noted the holes, but fitted in place.
Then he made a hole for the cable and glued it into place during the installation during the installation.
Unfortunately, hotmelt was not a good idea.Everything was fine in winter, but as soon as the lid got warmer, the button peeled off ... Now I fastened it on the reverse side and filled it with silicone sealant “Moment”, now it is holding tight.
Video: