I had recently purchased a used 2015 RAM 2500 Laramie truck privately and shortly after taking possession of the truck, I too discovered that I had the same problem with the instrument cluster lights remaining on after turning the ignition key to OFF position. I read up on this problem on this forum. I’ve also viewed other forum sites, performed many google searches, etc.
In my situation, if I was to open the door, and then close the door, the instrument cluster lights would stay on for about 12 seconds and then go out.
However, if I was to get into my truck, turn the ignition to the RUN position, and then back to the OFF position, and then get out of the truck, my instrument cluster lights would remain on for about 10-12 minutes. It didn’t matter if the engine was started or not. All I needed to do was to have the key in the RUN position for this repeatable event to repeat itself.
I spent many hours doing homework and research on the internet. I estimate that I spent about 15-20 hours doing my own research and trouble shooting.
I used an ODB reader to capture the diagnostic logs. This didn’t help me much as I had a couple of pages of error messages.
I then started to check out all the normal connections and what have you. I checked for moisture in the connections and having good connections, no bent pins, etc. I pulled the wiring harness off of the HVAC control module. No luck.
I then started to work in the fuse box. I estimate that I pulled about 30 different fuses. My hope was to find the event that was keeping the Body Control Module energized for the 12-12 minutes.
In pulling the fuses, I was able to isolate the problem to the body control module. It was at this point, I gave up and took it to the local dealership for trouble shooting\repair.
I took it to the local dealership and I specifically asked to speak with the shop foreman. I explained to him what trouble shooting I had already completed. I gave him a detailed summary of all the trouble shooting tasks that I completed up to that point.
In this package, I also included a copy of all the relevant articles that I’ve read in this forum. I basically cut and pasted all the relevant articles into a word document.
I also suggested that since this would be a difficult issue to resolve, I asked if he had any talented electrical diagnostic technicians on his crew. This was no job for an apprentice. To my surprise, he stated that he would look into this issue.
The shop foreman did all the basic checks. He checked to ensure that all modules had the correct software versions. He then continued on with his checks and tests. After being in the shop for a day or so, the shop foreman suggested that we replace the body control module. I agreed. They replaced the body control module and this did NOT fix the problem. Ouch! Once the new body control module was installed, I was then charged for the module.
The shop foreman had opened a ticket with the FCA technical support team and they were both stumped on how to proceed.
So, they decided to check every wire going in and out of the body control module.
By doing this, they were hoping to identify the specific wire that was telling the body control module to “stay on”.
Eventually, they found the root cause. The signal was coming from the “Air Suspension Control Module”. They suggested that we order in a new module to the tune of $1200. Ouch! I agreed as I really wanted to get this issue resolved.
The next day, the shop foreman was speaking with the FCA technician, and they thought of an idea. They verified that the software code on the ASCM was at the current version. The idea was to simply re-apply the software back onto the ASCM module as this task only takes about 5 minutes. They didn’t have anything to lose.
They re-applied the same current software back on to the ASCM module, and to their surprise, this WORKED. The problem was corrected and now everything works like it should.
At the end of the four day shop stay, I had to pay for the body control module (which they did not use, but did install temporarily), and for the shop labor. I was not charged for the new ASCM module as they did not install it. At the end of the day, they gave me a break on the labor costs and I thought the final bill was fair.
My hope is that this message may be of use to others out there. Especially those of you who have the rear air bags and air suspension control module.
Best of luck to all of you out there that have this problem.
