Apparatus and method of engine torque control during power take-off operation in a motor vehicle

An apparatus for controlling torque in a powertrain having an engine and a transmission capable of operating a power take-off unit, the apparatus comprising:

• a controller selectively operable to send a power take-off unit activation request to a transmission control module within said powertrain;
• the transmission control module capable of receiving said power take-off unit activation request;
• an engine control module operably connected to said transmission control module;
• a data link connecting said transmission control module and said engine control module;
• wherein said power take-off unit activation request is sent from said controller to said transmission control module through said data link;
• wherein said power take-off unit is activated when at least one enable condition is met,
• wherein said transmission control module broadcasts a maximum defined torque value across said data link, commanding said engine not to exceed said maximum defined torque value when said power take-off unit activation request is granted;
• a power take-off drive gear coupled to an input shaft on said transmission;
• and
• wherein said maximum defined torque value is greater than or equal to a torque rating of said power take-off drive gear in said transmission.

A method of controlling torque produced by an engine in a powertrain where the engine and a transmission are capable of operating a power take-off unit, the method comprising:

• sending a power take-off unit activation request to a transmission control module in said powertrain through a selectively operable controller;
• activating said power take-off unit when at least one enable condition is met;
• and
• implementing a program to prevent said engine torque from exceeding a maximum defined torque value, wherein said program includes:
• computing the maximum defined torque value and
• broadcasting said maximum defined torque value by said transmission control module to an engine control module in said powertrain through a data link connecting said transmission control module and said engine control module.