Note: If the screen displays a yellow exclamation mark 
when you're reversing the car, there must be a wrong wiring issue. You should refer the above wiring tips to check or you can check the wiring tips on our listing description.
Note: If the head unit’s without a CANBUS, it should have to connect the reverse cable as you shown on the picture below.
Dear @Mittens ,
Here is a wiring instruction of the D-Play model that you could refer to, if you have any confuse, please kindly indicate and let us know.
