Lost Right Rear Reverse Light

I am adding a reverse camera to my JSW to connect to my aftermarket ANS-810 head unit. I tapped into the reverse light power wire to trigger the camera each time reverse is engaged. I actually used this line to trigger a relay, the actual power feed to the camera is a 12V line that supplies the rear 12V accessory power connector.

After tapping the lines I have run into a problem. I have no power on the right reverse light wire. The bulb is fine, it is the wire without any power when I place the vehicle in reverse. Needless to say, I have no reverse camera video either.

I have checked the fuses and think I have found the one that handles this circuit and it looks fine. If someone could confirm the fuse that handles this just to be certain I would appreciate it.

I even stuck a pin in the wire upstream of where I spliced into the wire (I soldered my splices) and tried to see if I had 12V power in the wire prior to where I had done work on it. With the vehicle in reverse...zero volts.

Any ideas on how to trouble shoot? The wire I tapped was the blue/black wire on the rear light connector.

schultp said:

I am adding a reverse camera to my JSW to connect to my aftermarket ANS-810 head unit. I tapped into the reverse light power wire to trigger the camera each time reverse is engaged. I actually used this line to trigger a relay, the actual power feed to the camera is a 12V line that supplies the rear 12V accessory power connector.

After tapping the lines I have run into a problem. I have no power on the right reverse light wire. The bulb is fine, it is the wire without any power when I place the vehicle in reverse. Needless to say, I have no reverse camera video either.

I have checked the fuses and think I have found the one that handles this circuit and it looks fine. If someone could confirm the fuse that handles this just to be certain I would appreciate it.

I even stuck a pin in the wire upstream of where I spliced into the wire (I soldered my splices) and tried to see if I had 12V power in the wire prior to where I had done work on it. With the vehicle in reverse...zero volts.

Any ideas on how to trouble shoot? The wire I tapped was the blue/black wire on the rear light connector.

Click to expand...

Try coding byte 18 to bit 55 and see if that restores your backup light

Jeffbucc said:

Try coding byte 18 to bit 55 and see if that restores your backup light

Click to expand...

Well, I finally tried this....no luck. I changed it back to 00 to keep it at its default.

I checked the rear backup lights, right and left under the Advanced setting. When I engage the manual transmission in reverse the reading for the left goes to 99.6%, the reading on the right stays at 0%. So, I must have a break in the circuit...I just can't seem to find out where!?!

This is very frustrating. I'll work on it more today and hopefully have better news.

Here is the mods I made to add the reverse camera to my JSW. I am using the right rear reverse light to trigger a relay to pass 12V to the camera. The 12V power comes from the 12V power outlet in the right rear of the cargo area.

It isn't the best pic but I am asking if folks can review and make sure I have mapped out the connections properly...

Well I'm not a wiring expert but wouldn't the relay cause power to be lost to the reverse light when triggered for the camera? You could probably tap into the trunk accessory power port wire for the power?

No, the relay is triggered by voltage on the reverse power line which goes hot when the reverse gear is engaged. This should trigger the relay to switch on the 12V power that was tapped from the accessory 12V power port wire.

I am absolutely not getting any power on the reverse light power line. I have redone the connections and retested multiple times. I am confident it is not at the connections. I am wondering if the ECM settings were altered somehow. I know that in non-NAR VW (ie, european and others) that there is only one side that is the rear reverse light and the other is the rear fog light. I have tried playing with byte 18 in the Central Electronics Module (09) in VCDS but could not get the right rear reverse light to activate.

Using the Advanced Measured Values module I can see that when I place the transmission in reverse that I get a reading of full voltage to the left rear reverse light but a reading of 0% to the right rear reverse light.

I am ready to give up on this one and just drive with only one reverse light.

I did change some of my grounding wires to avoid splicing into the small brown grounding line on the rear light connector. Here is my updated schematic:

No bulb out warnings for the rt rr reverse lamp?
What is you disconnect terminal 86, does the lamp work then? ie: 12V present? If so, them another thing to try, is depending on the relay's internal construction, there may be a diode across the coil terminals, known as a flyback diode to quench the DC arc that can occur when the voltage in a coil rapidly decays when it's turned off and can weld contacts together in other switches and relays. Relays with these diodes generally require the positive feed on terminal 85 and the ground on terminal 86.
Did you return byte 18 to the original setting? It was not 00, which is only a mask.?

When I first directy connected the reverse camera power line to the 12V power line for the right rear reverse light, the light stopped working and I got the bulb warning dash light. I then changed to the relayed power feed and no longer have the bulb out indicator dash light.

I returned the byte 18 to a setting that I found on one of the vortex threads...can't remember the setting right now but it was the default for a JSW (...maybe 55??)

I've been driving with no right reverse light and no reverse camera. I've been fed up with the whole mess. You are spurring me to try switching terminal 85 and 86 connections.

I'll have a chance this coming weekend. I'll post an update at that time.

Did you guys ever figure out the cause of this issue. I too have the right reverse light out after connecting the backup camera trigger on black with blue stripe wire from the connector. Now my reverse light is not working. Bulb is good but there is no signal or voltage on the wiring.

I finally fixed this issue. My battery started losing its charge and had to jump start it a few times. My blinker was not audible but flashing normally so I bought a new battery. When I did that everything started working including my right reverse light. I tapped in my rear camera to the right harness and it works.

I was having the exact same problem with my backup light not working on the side i recently tapped for a backup camera. I tried everything to fix it all day this Saturday. After reading this post I was finally able to fix it by simply disconnecting the battery for a minute and reconnecting. Not sure why this fixes it, but I was so happy when it worked. Wish I had found that out a day earlier. Thanks for the help.