Umexpected power on backup light circuit
Thread Starter
Intermediate
Joined: May 2020
Posts: 27
Likes: 4
From: Florida
Umexpected power on backup light circuit
I have a 99 convertable that I'm installing an Alpine W650 in. Everything went smoothly until i started the motor. When i switched from ACC to ON. I'm getting 3.5 volts at the backup light, which tells the head unit to go to backup camera mode. When i put it in reverse (M6) i get 12 volts and the camera activates as it should. I've replaced the ignition switch, backup relay and cleaned the grounds. I checked the codes and found a B2482 H.
I've searched for similar issues on this forum and on Google and not been able to find anything similar. Hoping one of the experts here can help me out. Thanks.
I've searched for similar issues on this forum and on Google and not been able to find anything similar. Hoping one of the experts here can help me out. Thanks.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,621
Likes: 4,066
From: Cape Coral, Florida
Did you use some type of PAC harness interface with your installation ??…do you see 3.5 volts on the light green wire with ignition ON ??…maybe voltage is back feeding to that circuit from somewhere…if your in Southwest Florida being the car by…I just finished installing a Kenwood in my ‘08 yesterday and before the install while doing a test run I would get the 12 volts on the back up signal wire with the car in reverse with the engine not running…when I installed the PAC harness and did a test run no 12 volts in reverse…only when I had the car running did the backup camera work…that was a head scratcher…with my scan tool I didn’t see an input when in reverse so I’m thinking I have a BCM problem…I’ll look at some wiring diagrams and see what it may be
Thread Starter
Intermediate
Joined: May 2020
Posts: 27
Likes: 4
From: Florida
I'm reading 3.5 volts from initially, the power "pigtail" on the RCA connector from the camera feed. As i began checking, i read 3.5 volts friim both backup light sockets when the ignition is on. Ive checked all wires involved for shorts or broken or stripped insulation and reworked the camera ground wire. Stiil at a loss as to what is going on. Thank you.
