How can you force a vehicle built to operate in four-wheel drive to operate in two-wheel drive? Guidelines set by emissions certification agencies can require four-wheel drive vehicle manufacturers to answer this question. In many emissions testing procedures, the vehicle must run on a dynamometer, which requires two wheels to remain motionless while the remaining two drive wheels spin. For a vehicle that always runs in four-wheel drive, this mode of operation is impossible.
When faced with this problem for Land Rover vehicles, Jaguar and Land Rover used MathWorks tools and MICROGen target hardware from add2 Limited to emulate the controller for the transfer case in the transmission. This solution enabled Jaguar and Land Rover to operate the vehicle in two-wheel drive and achieve emissions certification from the Environmental Protection Agency (EPA) and other agencies without a problem.