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Determining the Contact Point (M20 MTA) Determining the contact point - TECH 2 main menu: "Programming" - submenu: "Program control unit The contact point is the position at which the pressure plate and the clutch plate come into contact with each other and transfer a small amount of torque (approx. 4 Nm ). The control unit is delivered with a pre-set contact point. This value will vary due to the different clutch and vehicle tolerances. Therefore, this parameter must be determined when the vehicle is commissioned. It is essential to determine the contact point before the clutch transfers higher levels of friction energy for the first time, so that premature damage to the clutch may be avoided. To prevent this, the control unit contains a test which ensures that the contact point is determined using TECH 2. If not, a fault code is stored and a quick contact point determination procedure is performed after each start. During this procedure, the transmission cannot perform any gearshifts. Even after this quick procedure has been carried out, it is not possible to shift all the gears. In this instance, the control unit only permits the neutral, 1st gear and reverse positions. This is necessary in order to prevent damage to the clutch or transmission. Once contact point determination has been carried out correctly, all gears are available again. Procedure for determining the contact point The procedure for determining the contact point takes approx. 20 seconds. At the beginning, the control unit uses a default value for the contact point. The procedure is as follows:
The contact point value stored in the control unit's EEPROM is a mean value of the various measurements. The quick procedure for determining the contact point works in the same way, but the clutch is not closed between the individual measuring procedures.
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