Method for operating a motor vehicle comprising a power take-off unit

A method of operating a motor vehicle with a motor, a driving transmission having at least one shifting element, a power take-off and a power take-off clutch by which the power take-off can be coupled to the driving transmission, the method comprising at least the following steps:

• detecting (10) a request to couple the power take-off;
• checking (12) whether respective boundary conditions for coupling the power take-off are fulfilled;
• if the respective boundary conditions are fulfilled, building-up (16) a system pressure sufficient for actuating the power take-off clutch;
• checking (18) whether a system pressure sufficient for actuating the power take-off clutch has been built up;
• if sufficient system pressure has been built up, producing (20) a confirmation signal that actuation of the power take-off clutch is permitted;
• and
• modifying (34) a driving transmission control unit in reaction to the confirmation signal, in order to actuate the at least one shifting element of the driving transmission with a higher actuation pressure than with an unmodified driving transmission control unit.

The method according to claim 12, further comprising calculating an actual torque at a drive input of the driving transmission as a function of at least one of the following parameters:

• a torque provided at the crankshaft of the motor;
• a consumer loss;
• a motor braking force when driving downhill;
• and
• a calculated torque applied on the power take-off.