Reverse light signal
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Joined: Jun 2014
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w163
Reverse light signal
I have a 2000 270cdi, and I am atempting to instal a rear camera.
I tried measuring the power at the backup light, and I got 8v all the time, and 12volt when the light turned on. I thought this was strange, and ran the wire outside of the car to the head unit. The head unit thought I was backing all the time, but the camera only turned on when the car was i reverse.
So I checked the wire behind the head unit for the command, and that gave me constant 12v or no v at all.
Then I disasembled the box around the shifter, and tried the wire that sends signal from the shifter. wire 9 acording to some sources on this forum, but that wire had 12v all the time..
Is there another way to get the head unit to turn on ONLY when the car is in reverse?
I tried measuring the power at the backup light, and I got 8v all the time, and 12volt when the light turned on. I thought this was strange, and ran the wire outside of the car to the head unit. The head unit thought I was backing all the time, but the camera only turned on when the car was i reverse.
So I checked the wire behind the head unit for the command, and that gave me constant 12v or no v at all.
Then I disasembled the box around the shifter, and tried the wire that sends signal from the shifter. wire 9 acording to some sources on this forum, but that wire had 12v all the time..
Is there another way to get the head unit to turn on ONLY when the car is in reverse?
Newbie
Joined: Aug 2013
Posts: 3
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1999 ML430
Do your reverse lights operate normally? I think I recall connecting my head unit to the grey wire in the radio harness for the reverse signal. You can pick up power for the camera in the trailer hitch harness behind the access panel just aft of the first aid kit compartment by connecting to the same grey wire.
