The vehicle was going into limp mode intermittently when travelling on an expressway or freeway up a hill. The dash displayed a DSC fault, and the fault could not be replicated on a dyno or on flat road. The fault generally occurred at high speed when more power was applied from a light throttle cruise.

The vehicle was standard apart from an EGR delete and an electric brake controller. The fault had been investigated by multiple workshops before presentation. Previous work included replacement of the MAP sensor, MAF sensor, air intake tube, ABS module and instrument cluster. The EGR delete had also been programmed into the engine ECU.

Initial testing found random CAN communication fault codes occurring with different modules and no consistent pattern. A previous second-hand ABS module had corrected implausible brake pressure readings, but the vehicle still entered limp mode at freeway speeds.