How to – Unichip Launch Control using Pin A4

How does Launch Control work. 

Basically we will set a rev limit at what ever the RPM we want the launch control to be active at. But first we need to find the clutch pedal position switch (all modern vehicle are equipped with one). Once you find the switch – it should be mounted somewhere above the clutch pedal – you need to test the signal going output to the ECU, it will either be a high (12 volt) signal or a low (o volt signal). Take a look at the picture below which is from a Scion FR-S which will output a 12 volt (high signal) in the rest position and 0 volt (low signal) when pressed down all the way.

Clutch Switch used for launch control

Clutch Switch used for launch control

 

Just to make double sure we will test the output from the clutch pedal switch (the signal to the ECU) with a voltmeter. Connect a one lead to the wire going to the ECU as in the picture below. In this case the voltage will be low (close to zero volts) with the clutch pedal pressed down all the way. If  you take your foot of the clutch pedal the voltage will return to high (12 volt). 

 

Once the wire output is confirmed you connect the wire as per the drawing above. The next step is to download the map form the reflash maps library to reflash your Unichip, if your map does not exist then send us a email and we will add it for download. If you want to take it one step further you can purchase the Unichip Tuning Software which will allow you to set the launch control value to any RPM between idle and red line. You can buy the Unichip launch control kit at this link