When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I grabbed 2 sets of 3156 from JDMStar and Vleds and I've got the same issue with both. When I plug in the bulbs they remain on at all times, if I have the truck in park or drive they shine at 50% output and if I throw the truck in reverse they bump up to 100% output. Another interesting part is that if I plug in just one LED and one factory bulb the problem stops. I'm wondering if having CK sockets could be the culprit or if I have a bad ground.
I just realized you have a 2015 not 2018, reading too many threads this morning I guess. Sorry, I know the 2018 bulb is supposed to be different and even the manual calls it out wrong.
Last edited by wadekaminski; Dec 8, 2018 at 11:59 AM.
I grabbed 2 sets of 3156 from JDMStar and Vleds and I've got the same issue with both. When I plug in the bulbs they remain on at all times, if I have the truck in park or drive they shine at 50% output and if I throw the truck in reverse they bump up to 100% output. Another interesting part is that if I plug in just one LED and one factory bulb the problem stops. I'm wondering if having CK sockets could be the culprit or if I have a bad ground.
Anyone ever dealt with this type of problem?
Never seen this mentioned before. But my guess it is the CK socket, somehow your getting back feed. I just don't understand if they are reverse lights, you should not have any voltage in the circuit unless the vehicle is in reverse. http://www.vleds.com/ck
From what I saw of a CK socket, it is for your turn signal/parking lamps where you have 3 contact points, turn, parking and ground. A reverse lamp is only two contact points.
Never seen this mentioned before. But my guess it is the CK socket, somehow your getting back feed. I just don't understand if they are reverse lights, you should not have any voltage in the circuit unless the vehicle is in reverse. http://www.vleds.com/ck
From what I saw of a CK socket, it is for your turn signal/parking lamps where you have 3 contact points, turn, parking and ground. A reverse lamp is only two contact points.
I'll take a look to see what type of socket I have by using Vleds pictures. If it is a CK type can I 1.) throw a set of CK specific bulbs in or 2.) remove the CK socket and replace with standard?
I'll take a look to see what type of socket I have by using Vleds pictures. If it is a CK type can I 1.) throw a set of CK specific bulbs in or 2.) remove the CK socket and replace with standard?
Well, if things work fine with the regular bulbs in, you don't have a bad ground. I swapped my regular bulbs to led bulbs in my reverse lights and have had no issues.
I will mention this again though, everything I have found for a CK socket is for turn signal/parking lights, not the reverse light. Polarity is also important for the led, try flipping it around and plug in again.
Well, if things work fine with the regular bulbs in, you don't have a bad ground. I swapped my regular bulbs to led bulbs in my reverse lights and have had no issues.
I will mention this again though, everything I have found for a CK socket is for turn signal/parking lights, not the reverse light. Polarity is also important for the led, try flipping it around and plug in again.
I was thinking the same thing when it came to a bad ground but I was pissing in the wind. I'm checking the socket today at lunch time and will load up my results, also I did try flipping the bulb around along with swapping sides with no clear results.
Sounds to me like the BCM continues to output a small amount of current even when the light is supposed to be off. Most likely won't be noticed with incandescent bulbs but is noticeable with LED's. The reason could be leakage current sometimes associated with solid-state electronics but my SWAG says it is to detect short or open circuits in the bulbs/wiring.
Got a chance to check the bulbs and socket and sure enough they are not CK versions.
I made sure to check that they were flipped the correct way and I even looked to see if there was a error on my dash about a bulb being out.
Definitely a standard socket for a reverse light. The only thing I can guess would be the LED's are drawing to low a current. When you put the standard bulb on one side, it puts enough load in the circuit to prevent it. I have no idea why I have no trouble with mine or many other people that have changed reverse bulbs. Looking at the wiring diagrams for a 2015, both reverse lights go to the same ground and both get fed off the same output on the BCM. I used LED's from www.f150leds.com when I did mine several years ago.
Definitely a standard socket for a reverse light. The only thing I can guess would be the LED's are drawing to low a current. When you put the standard bulb on one side, it puts enough load in the circuit to prevent it. I have no idea why I have no trouble with mine or many other people that have changed reverse bulbs. Looking at the wiring diagrams for a 2015, both reverse lights go to the same ground and both get fed off the same output on the BCM. I used LED's from www.f150leds.com when I did mine several years ago.
I'm willing to try a different set of bulbs especially ones that have been used by so many customers. I went ahead and messaged www.f150leds.com to see if they have ever seen anything like this.
Reverse lighting issue
