SEAT Workshop Service and Repair Manuals

Mechatronic unit for the semi-automatic gearbox -J743 -: Install Before making contact with the mechatronics, first make contact with an object that has an earth → Anchor. Installation is carried out in the reverse order, noting the following:

–  Place the mechatronic control unit -J743- on the gearbox casing carefully.   Note t  The side cover was not dismantled during removal. t  For reasons of illustration, the cover on the side has been removed in the figure. –  Do not pinch wiring. Take care not to trap the cable. –  The mechatronic unit must be carefully fitted onto the dowel pins -arrow-. Make sure that the »sensor arm« is in -its assembly position-. –  Check that mechatronic unit is mounted correctly.

–  Hand tighten new bolts -1- to -10-. –  Tighten the bolts in the order shown, to 5 Nm + 90° (1/4 turn). –  First hook the cable -A- on the upper fastening tab and then on the lower tab -arrows-. –  Plug in the connector and fit it in socket.

–  Replace the two -O-rings- if the »old« mechatronic control unit is to be reassembled. –  Lubricate the O-rings with gearbox oil for DSG dual clutch. –  Clean the seal of the cover and the seal surface on the gearbox. –  Make sure that the seal is correctly fitted. –  Put the cover on the mechatronics. Do not attach any tubes in doing so.

–  Thread on and tighten new screws -arrows- in diagonal pairs and in stages to a torque of 10 Nm. –  Connect the connector of the mechatronic control unit of the DSG automatic gearbox -J743- and then turn the lock to engage it.

–  Fit new cover on the gearbox oil pump -A- and tighten the screws -arrows- in diagonal pairs and in stages to a torque of 8 Nm. –  Fit the cable support on the cover and tighten the nuts to a torque of 10 Nm. –  Connect the connector of the mechatronic control unit of the DSG automatic gearbox -J743- and then turn the lock to engage it. –  If fitted, fit the hose joining the intercooler and the booster air pipe → Rep. gr.21. –  Reassemble all vehicle components which have been removed.

–  Fit the cable support on the large cover and tighten the nuts to a torque of 10 Nm. –  Reassemble all vehicle components which have been removed. –  Connect the battery earth strap → Electrical system; Rep. gr. 27

–  Do not start the engine. –  The filter has to be replaced if the oil is dirty → Chapter. –  Connect → Vehicle diagnostic tester. –  Fit the oil tray -SAT 1100- under the drain plug of the gearbox.

–  Undo the drain plug -arrow- located near to the pendulum support.

–  Before screwing adapter for oil filling -VAS 6262 A- onto oil bottle, measure length of breather pipe, dimension -a- and shorten → Anchor. Dimension -a- = 210 mm   Note The dimension -a- is measured from the shaft (green area in the counting glass) of the adapter for oil filling -VAS 6262 A-.

–  Screw the adapter for filling -VAS 6262 A- hand tight into the inspection hole.

–  Shake the bottles before opening them. –  Top up with 3 litres of oil. –  To change the bottle, the valve must be closed or the adapter for the oil filling -VAS 6262 A- must be held above the gearbox. Then start the engine, check the oil and top up with oil when required. The adapter for the oil filling -VAS 6262 A- must remain installed. –  Check the oil level and top-up if necessary → Chapter. –  Install the noise insulation → Exterior body installation work; Rep. gr.50. –  Make the basic adjustment using the central diagnosis -VAS 505X-.