(2018 Ram Sport) Anti-theft System / Factory radio / Aftermarket radio / Can C Network

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WAR-RAM

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I'm experiencing an issue with my truck that hopefully someone can help me figure out.

1. My truck has a aftermarket radio.

2. The truck was somehow 'reset' after a nearby lightning strike. (lightning did not strike my truck)

Now there is a communication issue that I believe is caused by the fact that I no longer have the factory radio in the truck. I looked at the electrical schematics and it shows the can c network (which carries the pcm, tcm, abs, and eps modules from the star connector under the passenger side of the dash) goes through the security gateway, and then to the radio. I'm wondering if this is part of the 'anti-theft' system that won't allow communication with the major modules (pcm, tcm, etc.) unless all the factory components are present.

When I unplug the dash harness (inline dash rt), the EVIC immediately comes on, and the fobs, windows, lights, horn, etc. works. As soon as I plug in the dash rt harness, the EVIC immediately goes blank. At first I thought there was an open, a short, bad ground, and a bad harness. I've tested everything and even replaced the complete dash harness, and the dash rt harness with a brand new harnesses. Still no dice! I've even unplugged individual modules from the star c connector just in case a module has gone down. Again, no dice.

I cannot read any DTCs because the DLC is linked to the security gateway and because there is no communication with the can c network, I cannot access the pcm.

I currently do not have my factory radio, so I need opinions about this before I purchase another radio. I'm close to certain that the lack of the factory radio is the culprit here.

Please advise
 

SitKneelBend

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I'm experiencing an issue with my truck that hopefully someone can help me figure out.

1. My truck has a aftermarket radio.

2. The truck was somehow 'reset' after a nearby lightning strike. (lightning did not strike my truck)

Now there is a communication issue that I believe is caused by the fact that I no longer have the factory radio in the truck. I looked at the electrical schematics and it shows the can c network (which carries the pcm, tcm, abs, and eps modules from the star connector under the passenger side of the dash) goes through the security gateway, and then to the radio. I'm wondering if this is part of the 'anti-theft' system that won't allow communication with the major modules (pcm, tcm, etc.) unless all the factory components are present.

When I unplug the dash harness (inline dash rt), the EVIC immediately comes on, and the fobs, windows, lights, horn, etc. works. As soon as I plug in the dash rt harness, the EVIC immediately goes blank. At first I thought there was an open, a short, bad ground, and a bad harness. I've tested everything and even replaced the complete dash harness, and the dash rt harness with a brand new harnesses. Still no dice! I've even unplugged individual modules from the star c connector just in case a module has gone down. Again, no dice.

I cannot read any DTCs because the DLC is linked to the security gateway and because there is no communication with the can c network, I cannot access the pcm.

I currently do not have my factory radio, so I need opinions about this before I purchase another radio. I'm close to certain that the lack of the factory radio is the culprit here.

Please advise
There is a factory inline fuse that powers the radio. Have you checked it?
 
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WAR-RAM

WAR-RAM

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The fuse in the harness near the battery? Yes, sir.
 

SitKneelBend

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The fuse in the harness near the battery? Yes, sir.
I wasn't sure if maybe that fuse being out would cause a CANBUS issue with whatever aftermarket integration may be associated with your radio. Is there a separate CANBUS module for your radio or is it all integrated?

Sometimes when lightning strikes near it can send out much smaller "forks" that strike nearby and aren't nearly as noticeable. I wonder if maybe something did get your truck? A personal anecdote, when I was younger lightning struck the neighbors house across a small parking lot, it caught that building on fire but a smaller streamer entered our house through a stain glass window went down the hall and out another window leaving only a smudge of carbon on the glass. If we hadn't seen it happen we would never have known it occurred...

All this to say, electrical gremlins like this are the worst.
 
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WAR-RAM

WAR-RAM

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I used the Pac Audio system with a Dual radio.

I'm certain that lightning didn't directly hit the truck. It hit a nearby tree and I think it may have gone through the roots under my driveway.

When the incident happened, I went outside and my rear brake lights and my radio was on. The cluster was blank. While the radio was on, it was not functioning.

I've taken the truck completely apart. I've replaced the dash harness and the harness that goes through the firewall on the passenger side. The weird thing is when I disconnect the modules that connect to the "DASH RT", my fobs, push start ignition, exterior lights, blinkers, horn, windows, power seats, radio, harzards, etc. works. The moment I connect the DASH RT harness, everything stops working.

The modules on the DASH RT are the PCM, TCM, EPS and ABS. I've indivually removed each module, and the module that appears to bring down the instrument cluster is the ABS. As soon as I disconnec the ABS module, the instrument cluster comes on, but nothing else works. Even when I remove the PCM, TCM, EPS and ABS modules from the "star connector" and leave the harness connected, the instrument cluster is the only thing that will turn on.

I know the PCM is good because it is my stock PCM. The PCM that was in the truck when lightning stuck the tree, was my tuned PCM.

I hate to throw a bunch of parts at the truck, but I'm thinking maybe the BCM was damaged and maybe even the TIPM.
 

SitKneelBend

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Yeah, definitely sounds like it got forked judging from your observations immediately after.

You may get some traction by asking if anyone has any spare parts/modules lying around (many do) and offering to pay shipping to test (then buying outright if it fixes your problem)? Couldn't hurt to post something in the want to buy section?
 
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