Fixed or Variable voltage

[heavymetalbebop]

I'm installing a backup camera and there are two wiring methods for the camera: one for fixed voltage and one for variable voltage. Does this vary by head unit or vehicle and which method should I use?

 

[Brian3676]

What kind of head unit do you have? Usually you select negative/positive, or it will call it ground/battery. Its asking what signal you want to use to turn the camera on.

 

[heavymetalbebop]

What kind of head unit do you have? Usually you select negative/positive, or it will call it ground/battery. Its asking what signal you want to use to turn the camera on.

Ok well I've got a pioneer and my polarity options are battery or ground. I've got the camera powered to the 12v wire behind the HU and polarity is set to battery but that setup is telling the HU to keep the camera on constantly- I get a black screen with parking guides when I start the car and the camera comes on when I go into reverse. Do I need to draw the power from another source? If I switch the polarity, it doesn't turn on at all.

I appreciate the help. I think I've tried every wiring configuration at this point and I'm ready to clip the wires and smash the camera :boom:

 

[Brian3676]

You need to tap the camera wire signal into the reverse light switch/wire. From what I understand you currently have it powered on at all times.

 

[heavymetalbebop]

Ok the camera must have an extra wire. It's powered into the reverse lights already so that's probably causing the confusion. I'll disconnect the 12v and see if that takes care of it. Thanks again!