The remote control module of central locking in Volkswagen Golf 3

[Vermes]

The aim of making this device is to make the Volkswagen handling easier by using the multifunctional remote control.
First useful element is a driver with two remote controls (penknife type). It has the following functions: open/close, additional canal, indicators.
This driver is designed only to control the electric actuators, so it is necessary to transform it a bit in order to adjust it to the new needs. A separate microcontroller is essential. The most proper is ATTINY2313. The original microcontroller from the driver is functional during the code identification. Then ATTINY is responsible for the rest.
Firstly, a prototype should be made. It's ATTINY linked with wires with the original plate:



Then a program is written in BASCOM.
When it's finished, an aesthetic look is next thing worth considering. The plate was designed in Eagle, tinned and made by thermal transfer method.



Next step is to place all elements in an original housing of the driver:



The driver has the following functions:

• a changeable keyloq code (there is HCS301 in the remote controls)
• detection of the opening/closing with the key
• self-arming (after the opening with the remote control, it is necessary to open the driver door within 20 sec, otherwise the car would close shortly)
• an additional canal
• detection of the ignition turned on (opening/closing doesn't work, additional canal works)
• windows closing (after the closing, the close signal (+) about 20 sec)
• signalization with the indicators

Pictures below show the remains after the used plate.



Link to original thread (attachments and films) - Moduł zdalnego sterowania centralnym zamkiem VW Golf 3