Attached are images of the wiring harness that came with the truck along with the power control unit on the driver side of the engine compartment. The wiring harness does not look like the previous wiring kit that came with the aux switches on my '19. I'll prob have to remove the front bezel in the cab, but it definitely looks like there will be room for the 4 aux switches. I just need to find the part number for that. If anyone has a 2025 on order with the stand alone Aux Switches, can you give me your VIN so I can try to look up the part number on the switch?
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2025 ram 3500 Limited option missing
- Thread starter regal2800
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That wiring kit is for the VSIM. You don’t have any aux switch wiring present on the truck either. So, I have no clue what they would mean when they say aux switch prep, because it’s not prepped at all.Attached are images of the wiring harness that came with the truck along with the power control unit on the driver side of the engine compartment. The wiring harness does not look like the previous wiring kit that came with the aux switches on my '19. I'll prob have to remove the front bezel in the cab, but it definitely looks like there will be room for the 4 aux switches. I just need to find the part number for that. If anyone has a 2025 on order with the stand alone Aux Switches, can you give me your VIN so I can try to look up the part number on the switch?
superjoe83
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Those harnesses look like the ones that come with the VSIM, im assuming your truck has that option?Attached are images of the wiring harness that came with the truck along with the power control unit on the driver side of the engine compartment. The wiring harness does not look like the previous wiring kit that came with the aux switches on my '19. I'll prob have to remove the front bezel in the cab, but it definitely looks like there will be room for the 4 aux switches. I just need to find the part number for that. If anyone has a 2025 on order with the stand alone Aux Switches, can you give me your VIN so I can try to look up the part number on the switch?
For those who think its gimmicky
The option is really cool to have a full rear view while towing. I also love the idea of having the knob in the event its needed - I've been towing for ~20 years without one, but it would have sure come in handy several times where I had 1/4 mile plus in reverse due to a flood, and an overhanging tree. During covid I got really sick and my wife had to drive the rig for the first time - would have been handy then (for both me and her, and now my son is driving)
Regardless of what one thinks of the feature, it is on the sticker as an option with a $$ associated with it - people are paying for this feature.
This is line item on the window sticker - its sold as a $1,490 feature.
View attachment 84315
The build code is LH2, under the Tow Tech Plus (AVS) - so yes, any dealer can order it under AVS.
View attachment 84316
With that out of the way, the OP and I (I'm assuming many other people are in the same boat) would like to know what LH2 means - what is this prep group? The distribution block?
H.O. said, in another thread, that this is on every truck, so that's not any kind of special "prep". Its standard. You should not be charged an additional option fee for something that is standard.
The matter is analogous to ordering the "Towing Prep" group in Max Tow for $2,330, and not getting a 7pin, or the puck system. You just might be asking yourself WTF did I pay for? This is the issue, and I would expect an explanation in the very least - ideally, I'd like some kind of aux switch prep, as that's what I'd paid for.
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Hardly, as the "Auxiliary-Switches Prep" is not the same thing as "Instrumented Panel Mounted Auxiliary Switches". It would be like saying the 5th wheel prep should come with a 5th wheel hitch and GN ball.
Other prep kits indicate that there is an additional item that can be purchased/used, such as 5th wheel prep, aux camera prep, etc...
The presence of a aux switches prep likely means that Ram currently, or at some point, planned to offer an aux switch retrofit for the trucks equipped with it. Nothing has been advertised yet, so who knows if it will actually happen.
I get it - they are not the same, but I'm not talking about instrument panel mounted switches. I'm referring to the line item as it pertains to prep for auxiliary switches (wherever you decide to mount them).
The tow prep does not come with a hitch, it comes prepped - you provide the hitch.
I planed on using one of the blanks to mount my switches (4wd bank, or the overhead, or even a standalone pod). Having a passthrough and fuse block prepped saves me a lot of time and effort - I need only the pigtail and the intermittent switch. That's an awesome option IMO - if it only existed.
The thing is, this “prep” has been an option since 2023 (since trailer reverse steering came out), and there is absolutely zero difference in wiring between a truck that has the “prep”, and a truck that doesn’t. Just trying to figure out what exactly the feature is, since Ram is notorious for not explaining things like this.
100% When my truck arrived, the prep (pigtails) were the first thing I looked for.
I purchased 02 (vp44) new, that had the tow wiring prep and the harness was in the door pocket. My 08 (cp3) had the brake controller harness and other wiring also in the door pocket.
Now with the 25 (cp4v2/8), no harness - just a widget. This is what lead me back to you guys. I got some catching up to do, but I'll share whatever I find with corporate/dealer - whoever has the answers.
Thanks to everyone for sharing - I've benefitted greatly from the knowledge on this forum
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That's part of the confusion, the pigtails are part of the installed aux switches. Based on how Ram does other "prep" kits there wouldn't be any wiring/pigtails/etc provided.
It would be really nice if Ram published something on the prep kit, but they haven't and with no differences in the wiring harness it seems like the probably won't.
To be 1000% clear, I did not say every truck. I said "every diesel." The association of this with LH2 or any other feature is inaccurate.
Every diesel has an AUX PDC populated with 3 50A fuses and 3 relays for the electric cabin heaters. There's no additional wiring present.
Yes, you did not say every truck. I misquoted you, and I'm sorry for that.
My point in bringing up LH2 is that there seems to be no difference in the auxiliary wiring between a diesel truck with the auxiliary switch prep (LH2) or any other diesel truck. The PDC is there, on every diesel.
Hence the question, what is the auxiliary switch prep (LH2), if not a passthrough and a PDC?
Just a heads up. I spoke with my dealer today and they are going to help help me figure this out.
They were not entirely sure what the prep entails, but were going start by looking for a similar config in the current inventory. If the tech couldn't explain, they would go to RAM to disclose what LH2 is comprised of.
I'll report back
They were not entirely sure what the prep entails, but were going start by looking for a similar config in the current inventory. If the tech couldn't explain, they would go to RAM to disclose what LH2 is comprised of.
I'll report back
Poking around some other forums (Jeep), I think LH2 is possibly just the sales code that enables the Aux switches in the BCM/EVIC, but no wiring or switch panel present...
Thanks, that's Interesting - so just on the BCM. So the software is prep'd.
If we get to RAM, I'll ask them how they intend to have the user installed switches interface with the hardware. From a practical standpoint, this could be a phantom/ghost feature.
I mean, AI is great for asking what 2+2 is, but that right there is a perfect example of why you can’t use it for stuff like this…
Yeah, I'd not intended it as a substitute for pursuing RAM's answer, but I will admit that AI seems to have some of the same assumptions I had when I was purchasing.
BTW - I'd also not checked the citations, knowing I would eventually be getting an answer from an authoritative source.
If you go to commercial settings in the screen set up page of the instrument cluster, do you have aux switches in there?
I had fooled around with that but ran into "pin setup" - I didnt want to lock myself out of anything so I aborted that exploration. I'll explore the commercial settings at lunch and report back.