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Discussion Starter · #1 ·
Hey, all! Looking for a bit of help with my aftermarket backup camera wiring. I've got everything installed as it should be, but it seems that the trigger wire that's connected to the positive reverse light wire (yellow/white) is losing power shortly after the car is put into reverse. This results in the head unit leaving the backup screen entirely, although it may return to the backup screen after a few seconds... I've heard that the reverse lights might cycle through different voltages after initial power (perhaps to conserve bulb life?). Does anyone have an idea for a fix?

Many thanks!
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 119K miles NOKIAN WR G3 30K miles
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23,106 Posts
No idea for a fix, but exterior lights are not simple DC circuits. Does your backing light stay on?
 

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Hey, all! Looking for a bit of help with my aftermarket backup camera wiring. I've got everything installed as it should be, but it seems that the trigger wire that's connected to the positive reverse light wire (yellow/white) is losing power shortly after the car is put into reverse. This results in the head unit leaving the backup screen entirely, although it may return to the backup screen after a few seconds... I've heard that the reverse lights might cycle through different voltages after initial power (perhaps to conserve bulb life?). Does anyone have an idea for a fix?

Many thanks!
Looks like your camera problem.
 

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Discussion Starter · #4 ·
They do. It's as if the trigger wire coming from the head unit isn't getting a consistent current from the reverse light to keep the unit in "reverse camera mode."
I wonder if maybe I need to wire a relay in between?
 

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Discussion Starter · #5 · (Edited)
SOLVED!

I tapped the head unit trigger wire into the "accessory positive" line on the relay. This way, the positive reverse light wire triggers both the camera power and the head unit trigger. It doesn't seem like the relay trigger (blade 86) needs a constant 12v current, so once the reverse light is powered on (and even when the current varies), it allows the 12v constant current from blade 30 to pass through to the camera positive (blade 87) and simultaneously triggers the head unit to switch to the camera view. Brief summary of the relay connections below for anyone interested.

30: 12v constant (tapped into multi cd changer 12v constant)
85: ground (reverse light ground & camera ground)
86: trigger (reverse light positive)
87: accessory positive (camera positive and head unit trigger)

On to the next project!
 
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