Adding A Backup Camera To My 2005 Jaguar XJ8:
I've been driving this quite a bit lately.
I installed a backup camera but didn't want to use the suction cup mount on the windshield, and there wasn't room on the console because I have a mount there for my phone, so I stuck it to the dash with heavy duty Velcro.
The camera bracket sits behind the plate with the camera hanging over it.
The camera wire goes up into the trunk lid, goes through a rubber wire loom into the trunk, through a gromet in the center where I ran my antenna wire, and then follows the carpet trim panel along the driver side to the dash.
The power wiring proved to be a bit complicated.
Most vehicle lighting is grounded and comes on when you apply power. Jaguar for some reason sends power to the lights, and then activates it by grounding it.
The Orange and Green wire is the backup wire, but it's always hot (+). Once the car is put in reverse this wire is grounded (-).
To solve this problem, I used a relay. I didn't come up with this. I found this on a Jaguar forum.
This is how a relay normally works.
This is how I wired the relay on the Jaguar. This doesn't seem like it should work, but it does.
Relay:
30 To Brown / Green Wire (Tail Light)
86 To Brown / Green Wire (Tail Light)
85 To Orange / Green Wire (Backup Wire)
87 To Camera
It seems wrong to have power going to (85) when it's supposed to be a ground. It seems wrong to have power on both sides of the coil (86 & 85). I used a relay with a built-in fuse holder.
When the car is put into reverse, the Orange / Green wire (85) grounds the relay and sends power through (87) to turn on the camera.
So, when I prepared the relay, the two yellow wires are going to attach to the cars Brown / Green wire with a wiretap, and the white wire is going to the cars Orange / Green wire. The power wire for the camera will go to the empty prong (87) on the relay.
In case you noticed, there's marks from a marker on one of the yellow wires. Sometimes I put hash marks with a permanent marker on a wire so I can use it and tell it apart from the other wire of the same color.