reverse light

[20ducks]

Reverse light stays on all the time. Any idea why this is happening?

Sponsored

 

[smurfslayer]

any modifications?
any chance you’ve had a collision, no matter how minor?

 

[Aegean]

Assuming the rear camera comes on only during reverse which proves the gear selector sensor is fine, probably it is a wiring short to ground on the reverse light circuit. I doubt there is a setting in ForScan to set it on but I let more knowledgeable members to comment.

 

[20ducks]

No collisions. The only real mod has been that I hard wired a radar detector.

 

[smurfslayer]

Have you checked FORSCAN for BCM diagnostic trouble codes - DTC’s?

The reason I’m asking is I tripped the BCM once on my Raptor tapping power off the bed lights power - because I was too lazy to take the run to the battery for the relay. That was a poor life choice. It worked for about 30 seconds and the lights went dark, as did the 3rd brake light, cab lights, etc. I spent 15 minutes trying to and failing to find a blown fuse. I hooked up forscan and sure enough, DTC’s on the BCM. Cleared them and restored function. Ran power to the battery for my relay
- I was adding rear facing lights on switch and on with reverse.

I would check codes. You may think the radar detector has nothing to do with it - and maybe you’re right but it’s an easy check and it’s close-ish to the symptoms I saw.

I don’t know if you noticed, but the wires on the newer vehicles are VERY, VERY thin multi-strand wire. if you used a ‘vampire’ tap - or crimp connector, it’s very easy to compromise the wiring. If you noticed this already and properly made your hardwiring connections, feel free to disregard, I just wanted to cover the base.

 

[Aegean]

Did you hardwire the radar detector from the auto dim mirror wiring? One wire at the mirror is the reverse indicator circuit. When you put in reverse, it sends a 12V signal to that wire. That tells the mirror to not dim during reverse. Do you think the issue is in that wiring?

 

[dusman59]

Years ago people would wire their backup lights on as a drag race challenge. I cannot confirm or deny participating in this.

 

[20ducks]

I will pull the wires that I used off the mirror. In doing that will it stop the reverse light from coming on?

 

[Aegean]

I will pull the wires that I used off the mirror. In doing that will it stop the reverse light from coming on?

Yes. I would try disconnecting the radar detector first from the mirror wiring. if the reverse light turns off you are fine. Probably you got one wire wrong which completes the reverse circuit and remains on when the detector is on.

Another possibility is that you pinched a wire in the mirror harness and shorted but I hope not.

 

[20ducks]

Yes. I would try disconnecting the radar detector first from the mirror wiring. if the reverse light turns off you are fine. Probably you got one wire wrong which completes the reverse circuit and remains on when the detector is on.

Another possibility is that you pinched a wire in the mirror harness and shorted but I hope not.

You are a genius!! Had the white (power) and black (ground) wires connected correctly but somehow blended a few strands of a gray wire. Disconnected the gray and voilà!
Many thanks.

 

[Aegean]

You are a genius!! Had the white (power) and black (ground) wires connected correctly but somehow blended a few strands of a gray wire. Disconnected the gray and voilà!
Many thanks.

Tell that to my wife! I am glad you fixed it.

Sponsored