Regarding the class 101 2 car from Tees valley. With the front marker lights on, the wiper turns red/pink in colour.
It’s the BR Class 101 which has a bug with the windscreen wiper glowing red when the lights are turned on. It was a bug introduced in TSW3 I believe and has been reported before. It isn’t broken on all variants of the 101 in the game but is annoying when you get the one that is broken and have to drive with the right marker light off.