[SSD]

I watched several YouTube videos and different articles and posts in this forum.

I am still quite confuse for hooking up backup camera power source in a 2008 e90 non idrive

I can see ppl have different opinions:

1) direct to battery (front port of power distribution module or very front port on battery) with in line 15amp fuse and relay.

2) I see if connect to rear port of power distribution module is a no go as it will throw error code and the computer doesn't like it

3) I see ppl use add a circuit to tap to cigarette fuse (slot 8) in my model. But add a circuit rate for 10amp and cigarette fuse rate for 20amp.

4) I see ppl also said to use homelink or park sensor fuse. And my car doesn't have both feature.

5) I don't have CD changer. But I see a fuse at CD changer fuse. Can that be use?

6) There's also a post talk about the quality of the relay and use one said RL44 at the end is good. So I guess more expensive is slightly better? Or how do I know the quality of it if I don't try it before.

I want to try 1) as above so that I don't need to run any cable to the front (my camera is autovox m1w wireless model)

Any help will be appreciated

[Sp4rtanSD]

The answer depends to some extent on where the camera is mounted and what you want to do with it. Direct to battery is pretty easy and foolproof, but you don't usually want the camera powered up unless you are in reverse. You probably can't power it directly from the backup light wiring, but you can put a relay on that wire (it's in the harness right above the battery, black/purple). I think any general purpose accessory relay will work OK. You don't need one with a harness - you can plug spade connectors right on to it. Do get one with a mounting tab - there is a little stud up next to the wiring harness over the battery where you can mount it.

[SSD]

Thx.

The back up camera will mount as the license plate and definitely want to turn on whenever I reverse. I don't want it to turn on all the time as it has a sensor that if it is dark, it will turn on LED.

So I know I need a relay. But want to confirm that it is safe to get power direct from battery and must be from either of the two front positive plug on the battery /power distribution module in order to avoid throw out an error code. With relay, I don't expect it will drain the battery as long as there is a decent relay used.

Am I right?

[SSD]

I have a chat with a mechanic today and he warns me not to touch the battery in e90 as there's distribution module and IBS cable that are very sensitive and put the car in limp mode for mistake.

So now, I need to run a 18 gauge cable from trunk cover (I will put the relay inside the trunk cover if space allow) all the way to fuse panel. And use mini atm add a circuit

I think I will try fuse 19 (current has a 5amp fuse) and it shows for CD changer and I don't have CD changer in car. I guess it is safe to use.

If fail, I guess I need to use fuse 8 (currently has 20amp fuse) but add a circuit for mini atm rate for 10amp only, not sure if it will have issue.

[n2siast]

Don't know if this helps, but I didn't need a power source for the camera itself in the trunk. I only connected the white wire from the Camera Emulator in the front to the red wire connected to the yellow RCA connector then ground the camera in the trunk and my reverse cam worked, didn't need to use a separate power source. So, out of the 2 wires from the trunk, RED and Black, I only used the black. Red isn't connected to anything.

Yours could be wired totally different.

[SSD]

I don't have navigation or idrive. So I don't think I have that emulator in my car

[SSD]

Is it OK to tap the ground wire of the backup camera to the brown ground wire of the reverse light housing?

[SSD]

So far, I can successfully run two 16gauge wire to the conduit. My camera has a micro av with power integrated plug but I cannot get that via the conduit after many trials.

So I have the wireless transmitter stick to the trunk cover. One wire will tap to reverse (black/purple) then to relay near battery compartment. Another wire will connect to 12v to camera with other end on relay port 30. The camera has its own ground in the trunk cover that I plan to tap into the brown wire in the reverse light housing. Then relay ground will connect to the ground for main battery (I think there's a screw there)

Another 16 gauge will run from battery compartment to front fuse panel with fuse tap in slot 8, where original fuse will be 20amp and 2nd fuse will be 5amp.

I hope this will work without issue.