Having trouble seeing the brake lights in the broad daylight, running lights/turn lights? Try this suggested settings. You can adjust the level of brightness on each light to suit. 

Go in visualsettings.dat (update.rpf/common/data) and find these lines, then replace them:

# emissive bits
car.headlight.day.emissive.on	80
car.headlight.night.emissive.on	10
car.headlight.day.emissive.off	0
car.headlight.night.emissive.off	0
car.taillight.day.emissive.on	80
car.taillight.night.emissive.on	30
car.taillight.day.emissive.off	0
car.taillight.night.emissive.off	0
car.indicator.day.emissive.on	120
car.indicator.night.emissive.on	40
car.indicator.day.emissive.off	0
car.indicator.night.emissive.off	0
car.reversinglight.day.emissive.on	80
car.reversinglight.night.emissive.on	30
car.reversinglight.day.emissive.off	0
car.reversinglight.night.emissive.off	0
car.defaultlight.day.emissive.on	20
car.defaultlight.night.emissive.on	7
car.defaultlight.day.emissive.off	0
car.defaultlight.night.emissive.off	0
car.brakelight.day.emissive.on	100
car.brakelight.night.emissive.on	35
car.brakelight.day.emissive.off	0
car.brakelight.night.emissive.off	0
car.middlebrakelight.day.emissive.on	100
car.middlebrakelight.night.emissive.on	35
car.middlebrakelight.day.emissive.off	0
car.middlebrakelight.night.emissive.off	0
car.extralight.day.emissive.on	30
car.extralight.night.emissive.on	10
car.extralight.day.emissive.off	0
car.extralight.night.emissive.off	0
car.sirenlight.day.emissive.on		150
car.sirenlight.night.emissive.on	150
car.sirenlight.day.emissive.off		0.05
car.sirenlight.night.emissive.off	0.04
car.emissiveMultiplier	2
