I've had a situation in a late model 140chassis car where there was abnormal resistance to the first bit of movement of the brake pedal. Not where it was very difficult to press but there was more resistance at the first bit of travel than normal. There were no fault codes or warning lamps. Turned out that the cable that controls the park interlock was out of adjustment. Funny thing is that the interlock worked, the brake pedal just didn't feel right. The adjustment is near the brake pedal but its been too long to give an accurate description as how to adjust it. Maybe someone else can help with that procedure.