2018 Radio, CarPlay, Heated Seats stop functioning shortly after starting

[OtterlyFoolish]

I have a 2018 RAM 2500 Laramie with 6.4 HEMI that has been driving me nuts for months now. Radio, CarPlay & Heated Seats usually stop functioning shortly after starting but sometimes 20 minutes into my drive. Everything functions on the next start about half the time. Had three places check the battery, charging and starting systems because I started seeing "Battery Saver Mode" on the dash. One told me that the starter was causing problems so I changes that out along with the battery temp sensor at the negative terminal thinking that it was sensing a draw that wasn't there. The truck always starts without any struggle and I can leave it for weeks at a time without problems so I do not think there is a parasitic draw. I kept the original starter and battery sensor as spares seeing how they were not the problem.

In the past I had the 8.4 Uconnect radio delaminate and I replaced it with one from Amazon. Ran that radio for a year before these issues started without any issues. I bought another 8.4 Uconnect thinking that it was the problem but the same problems exist after replacing it a second time so now I have a spare radio too.

I also replaced the ABS HCU about a year ago with whatever part number superseded the original.

Other issues I have experienced are my compass reading completely off course as well as the ambient temp was sometimes dramatically wrong. I replaced the module in the overhead panel that I thought controlled the compass but it did not help but a new ambient temp sensor seems to have fixed that issue.

Other than what I have mentioned the truck has no mods or replaced parts. I have opened the TIPM and seed no signs of damage or corrosion but I cleaned it all thoroughly and put it back together. I see no visible signs of bad wires and I am now thinking that the BCM has to be the problem. I found this forum and figured that I would see if anyone here has experienced anything similar. I have searched everywhere and can not find another documented problem like mine. Everything related to "Battery Saver Mode" talks about the intake heater on the Cummings so I get no help there.

I have a OBDLink EX cable coming for my laptop as well as the Chrysler FCA Authorization Gateway Security Bypass Cable and plan on getting AlfaOBD as soon as the others arrive. Ordering a new BCM tomorrow unless I get some solid info from you all here.


Any help at all would be greatly appreciated.

 

[SitKneelBend]

I have a 2018 RAM 2500 Laramie with 6.4 HEMI that has been driving me nuts for months now. Radio, CarPlay & Heated Seats usually stop functioning shortly after starting but sometimes 20 minutes into my drive. Everything functions on the next start about half the time. Had three places check the battery, charging and starting systems because I started seeing "Battery Saver Mode" on the dash. One told me that the starter was causing problems so I changes that out along with the battery temp sensor at the negative terminal thinking that it was sensing a draw that wasn't there. The truck always starts without any struggle and I can leave it for weeks at a time without problems so I do not think there is a parasitic draw. I kept the original starter and battery sensor as spares seeing how they were not the problem.

In the past I had the 8.4 Uconnect radio delaminate and I replaced it with one from Amazon. Ran that radio for a year before these issues started without any issues. I bought another 8.4 Uconnect thinking that it was the problem but the same problems exist after replacing it a second time so now I have a spare radio too.

I also replaced the ABS HCU about a year ago with whatever part number superseded the original.

Other issues I have experienced are my compass reading completely off course as well as the ambient temp was sometimes dramatically wrong. I replaced the module in the overhead panel that I thought controlled the compass but it did not help but a new ambient temp sensor seems to have fixed that issue.

Other than what I have mentioned the truck has no mods or replaced parts. I have opened the TIPM and seed no signs of damage or corrosion but I cleaned it all thoroughly and put it back together. I see no visible signs of bad wires and I am now thinking that the BCM has to be the problem. I found this forum and figured that I would see if anyone here has experienced anything similar. I have searched everywhere and can not find another documented problem like mine. Everything related to "Battery Saver Mode" talks about the intake heater on the Cummings so I get no help there.

I have a OBDLink EX cable coming for my laptop as well as the Chrysler FCA Authorization Gateway Security Bypass Cable and plan on getting AlfaOBD as soon as the others arrive. Ordering a new BCM tomorrow unless I get some solid info from you all here.


Any help at all would be greatly appreciated.

I think you may be on the right track for the BCM. SOme of the things you described are things I saw when I swapped BCMs and it later settled in. Be sure to make a backup of your current BCM now before doing anything. Are you ordering a new or used BCM?

 

[OtterlyFoolish]

I think you may be on the right track for the BCM. SOme of the things you described are things I saw when I swapped BCMs and it later settled in. Be sure to make a backup of your current BCM now before doing anything. Are you ordering a new or used BCM?

Thanks for the fast response. I am ordering a new BCM. I do not want to waste time having to do that tedious work twice.

What problems were you seeing?

 

[SitKneelBend]

Thanks for the fast response. I am ordering a new BCM. I do not want to waste time having to do that tedious work twice.

What problems were you seeing?

Compass heading and outside temperature were off. There are a few things you can do to your current BCM before replacing it BUT sometimes it's nice to have the new one on hand just in case. The module in the overhead does in fact control the compass.

 

[OtterlyFoolish]

Compass heading and outside temperature were off. There are a few things you can do to your current BCM before replacing it BUT sometimes it's nice to have the new one on hand just in case. The module in the overhead does in fact control the compass.

I just really want my radio to work and head off problems before something major malfunctions when towing that could get someone hurt.

 

[SitKneelBend]

I just really want my radio to work and head off problems before something major malfunctions when towing that could get someone hurt.

Is it your daily driver or something you could wait for a new BCM to arrive if something went wrong?

 

[OtterlyFoolish]

Is it your daily driver or something you could wait for a new BCM to arrive if something went wrong?

I need it at least a few days a weeks.

 

[SitKneelBend]

I need it at least a few days a weeks.

Well, I'd probably wait until you have the backup BCM in hand before you do anything. Have you disconnected the battery yet? If not, leave it off for about an hour then reconnect. Also, any stored codes?

 

[OtterlyFoolish]

Well, I'd probably wait until you have the backup BCM in hand before you do anything. Have you disconnected the battery yet? If not, leave it off for about an hour then reconnect. Also, any stored codes?

I have left the battery out and even crossed the disconnected cables to drain any stored capacitor power. There is a P058C code stored. Battery Monitor Module Temperature Monitoring Performance. That is why I changed the battery sensor at the batteries ground terminal. It did not help and I can not clear that code.

 

[SitKneelBend]

I have left the battery out and even crossed the disconnected cables to drain any stored capacitor power. There is a P058C code stored. Battery Monitor Module Temperature Monitoring Performance. That is why I changed the battery sensor at the batteries ground terminal. It did not help and I can not clear that code.

Does it have two batteries? I'm not sure how those are wired but the goal I'm looking for for troubleshooting purposes is the remove power from all modules (including the BCM) to get them all to refresh their settings from the BCM when power is restored. That's the only thing that got my strange issues corrected after programming a new BCM for my truck.

 

[OtterlyFoolish]

Just the one battery. I had read that removing both battery cables for a period of time and then connecting them (off the battery) would force a hard reset on the BCM so that is the procedure that I followed. If I remember right it worked for a short time but started acting up again in a day or so.

 

[SitKneelBend]

Just the one battery. I had read that removing both battery cables for a period of time and then connecting them (off the battery) would force a hard reset on the BCM so that is the procedure that I followed. If I remember right it worked for a short time but started acting up again in a day or so.

Ok, here are some instructions I made for another forum member working on a project with me, the instructions aren't written directly for your situation but should help you with the swap...Just replace "2014" with "old" and "2016" with "new" and it should make sense for you. Also, I don't know if a brand new BCM comes loaded with any configurations so it may not be necessary to take a backup of it's factory configuration before uploading your trucks config to it (don't think it will hurt though. Also, there is no reference to a SGM bypass as we both were working on pre-2018 trucks but you will need the SGM bypass to get yours done on a 2018. Let me know if you have any questions...


1. Create an AlfaOBD Backup of your current BCM Config (Body Computer -> Body Computer My2014 Powernet -> Car WIth Hood Open Icon - > Select Procedure to start -> Backup Vehicle Configuration to File)

2. When Complete go to the Hammer and Wrench Icon in the top right of the app and select Upload to Google Drive (At this point use the sign-in button at the top of the screen if not already signed into your g-drive).

3. Select Upload Any AlfaOBD File -> BCM Config -> ConfigBackup(Todays date and time)

4. When Complete Go to your G-drive and and rename the file with "2014" at the beginning as you will be repeating this process later for the new BCM. You may also want to create a new folder and place all of the files you are going to create for this now.

5. Read the System ID and Status of your current BCM Config (Body Computer -> Body Computer My2014 Powernet -> Battery Icon - > Read System ID AND THEN Read System Status. This will create a readable/printable log of all your current setting selections not in Hex format but in English

6. When Complete go to the Hammer and Wrench Icon in the top right of the app and select Upload to Google Drive (At this point use the sign-in button at the top of the screen if not already signed into your g-drive).

7. Select Upload Any AlfaOBD File -> Faults and Status Log -> Body_Chrysler_Info

8. When Complete Go to your G-drive and and rename the file with "2014" at the beginning as you will be repeating this process later for the new BCM. Place the File in the folder you created if you did not save directly to that folder when prompted.

9. Take a look at both of the files you created but do not make any changes as that will corrupt the files. You should see a bunch of numerical codes in the BCM Config and a series of options programmed in the Body_Chrysler_Info File.

10. Proceed to remove the 2014 BCM from your truck (do this all with the negative battery cable disconnected and isolated from the negative battery stud). Start by unlocking/removing the connectors (there is a black plastic retainer in the middle you can pull out to move the wire harness as far out of the way as you can manage).

11. Remove the 4 (13mm?) bolts securing the BCM to the firewall. The top bolts are more easily accessed by removing the driver side dash tweeter (I use a plastic trim tool to remove the grille and I think they are 7mm screws). Once removed you will be able to access the two bolts at the top of the BCM (but it's still a tight space to work in.

12. There are 3 (13mm?) bolts holding the parking brake on, remove them. Once removed you can lay the parking brake down on the floor to get space to remove the BCM and install the new.

13. At this point, consider weather or not you need more space to get the BCM out by removing the factory Alpine Amp in this area. It will be a black ribbed module locate (somewhere) in this area.

14. Remove the BCM from the studs on the firewall and cuss and curse it out of it's mounting location.

15. Optional - compare the pins on the old and new BCMs (I took pictures, there was one difference on one of the connectors, I'm interested to know if you see similar)

16. Reverse steps 10-14 to install the new BCM.

17. When all Connectors are attached back to the BCM and locked in place, reconnect the Battery cable

18. Before uploading your old config, repeat steps 1-9 for the new BCM ensuring you rename the files with "2016" to identify them correctly.

19. DO NOT Turn on the ENGINE (insert the key to RUN but don't crank) To program the new BCM, you will need to Restore an AlfaOBD Backup of your current BCM Config (Body Computer -> Body Computer My2016 Powernet -> Car With Hood Open Icon - > Select Procedure to start -> Restore Vehicle Configuration from File). Ensure you use the 2014 file first created (BCMConfig*Todays Date*) . I can't remember but I think it will use the file directly on your phone instead of prompting you to choose a location on your G-Drive, just match the timestamp to the first backup you created for your 2014 BCM (this will be the hex format file).

20. If successful, it may be beneficial to remove the negative battery cable again for 15 minutes or so. This will reset all of the modules connected to the BCM that may have read information from the new BCM before restoring the old configuration.

21. Reconnect the negative battery cable and start the truck. Record any faults stored by reading them to the log file. It's important to note, that the log file(s) are continuous so instead of a separate file for each it will have a running list of what you have requested. You'll need to manually segment the sections in a text editor if you want to organize it better.

 

[OtterlyFoolish]

Ok, here are some instructions I made for another forum member working on a project with me, the instructions aren't written directly for your situation but should help you with the swap...Just replace "2014" with "old" and "2016" with "new" and it should make sense for you. Also, I don't know if a brand new BCM comes loaded with any configurations so it may not be necessary to take a backup of it's factory configuration before uploading your trucks config to it (don't think it will hurt though. Also, there is no reference to a SGM bypass as we both were working on pre-2018 trucks but you will need the SGM bypass to get yours done on a 2018. Let me know if you have any questions...


1. Create an AlfaOBD Backup of your current BCM Config (Body Computer -> Body Computer My2014 Powernet -> Car WIth Hood Open Icon - > Select Procedure to start -> Backup Vehicle Configuration to File)

2. When Complete go to the Hammer and Wrench Icon in the top right of the app and select Upload to Google Drive (At this point use the sign-in button at the top of the screen if not already signed into your g-drive).

3. Select Upload Any AlfaOBD File -> BCM Config -> ConfigBackup(Todays date and time)

4. When Complete Go to your G-drive and and rename the file with "2014" at the beginning as you will be repeating this process later for the new BCM. You may also want to create a new folder and place all of the files you are going to create for this now.

5. Read the System ID and Status of your current BCM Config (Body Computer -> Body Computer My2014 Powernet -> Battery Icon - > Read System ID AND THEN Read System Status. This will create a readable/printable log of all your current setting selections not in Hex format but in English

6. When Complete go to the Hammer and Wrench Icon in the top right of the app and select Upload to Google Drive (At this point use the sign-in button at the top of the screen if not already signed into your g-drive).

7. Select Upload Any AlfaOBD File -> Faults and Status Log -> Body_Chrysler_Info

8. When Complete Go to your G-drive and and rename the file with "2014" at the beginning as you will be repeating this process later for the new BCM. Place the File in the folder you created if you did not save directly to that folder when prompted.

9. Take a look at both of the files you created but do not make any changes as that will corrupt the files. You should see a bunch of numerical codes in the BCM Config and a series of options programmed in the Body_Chrysler_Info File.

10. Proceed to remove the 2014 BCM from your truck (do this all with the negative battery cable disconnected and isolated from the negative battery stud). Start by unlocking/removing the connectors (there is a black plastic retainer in the middle you can pull out to move the wire harness as far out of the way as you can manage).

11. Remove the 4 (13mm?) bolts securing the BCM to the firewall. The top bolts are more easily accessed by removing the driver side dash tweeter (I use a plastic trim tool to remove the grille and I think they are 7mm screws). Once removed you will be able to access the two bolts at the top of the BCM (but it's still a tight space to work in.

12. There are 3 (13mm?) bolts holding the parking brake on, remove them. Once removed you can lay the parking brake down on the floor to get space to remove the BCM and install the new.

13. At this point, consider weather or not you need more space to get the BCM out by removing the factory Alpine Amp in this area. It will be a black ribbed module locate (somewhere) in this area.

14. Remove the BCM from the studs on the firewall and cuss and curse it out of it's mounting location.

15. Optional - compare the pins on the old and new BCMs (I took pictures, there was one difference on one of the connectors, I'm interested to know if you see similar)

16. Reverse steps 10-14 to install the new BCM.

17. When all Connectors are attached back to the BCM and locked in place, reconnect the Battery cable

18. Before uploading your old config, repeat steps 1-9 for the new BCM ensuring you rename the files with "2016" to identify them correctly.

19. DO NOT Turn on the ENGINE (insert the key to RUN but don't crank) To program the new BCM, you will need to Restore an AlfaOBD Backup of your current BCM Config (Body Computer -> Body Computer My2016 Powernet -> Car With Hood Open Icon - > Select Procedure to start -> Restore Vehicle Configuration from File). Ensure you use the 2014 file first created (BCMConfig*Todays Date*) . I can't remember but I think it will use the file directly on your phone instead of prompting you to choose a location on your G-Drive, just match the timestamp to the first backup you created for your 2014 BCM (this will be the hex format file).

20. If successful, it may be beneficial to remove the negative battery cable again for 15 minutes or so. This will reset all of the modules connected to the BCM that may have read information from the new BCM before restoring the old configuration.

21. Reconnect the negative battery cable and start the truck. Record any faults stored by reading them to the log file. It's important to note, that the log file(s) are continuous so instead of a separate file for each it will have a running list of what you have requested. You'll need to manually segment the sections in a text editor if you want to organize it better.

Thank you so much for your help. I did purchase the SGM bypass. I think that the cables needed are behind my radio but I am a pro getting that in and out now. LOL

 

[SitKneelBend]

Thank you so much for your help. I did purchase the SGM bypass. I think that the cables needed are behind my radio but I am a pro getting that in and out now. LOL

No problem! That I am unsure of as I don't have a SGM in my 2014, but I think I heard the connection is under the steering wheel somewhere (for the star connector type bypass). There should be a lot of thread on here though explaining it.

I will re-emphasize make sure to make a backup of the BCM before doing anything. So many people skip this step and while it's not the end of the world you will save yourself a lot of time (and possibly money) by having a known-good config.

 

[Texasmd]

I have a 2018 RAM 2500 Laramie with 6.4 HEMI that has been driving me nuts for months now. Radio, CarPlay & Heated Seats usually stop functioning shortly after starting but sometimes 20 minutes into my drive. Everything functions on the next start about half the time. Had three places check the battery, charging and starting systems because I started seeing "Battery Saver Mode" on the dash. One told me that the starter was causing problems so I changes that out along with the battery temp sensor at the negative terminal thinking that it was sensing a draw that wasn't there. The truck always starts without any struggle and I can leave it for weeks at a time without problems so I do not think there is a parasitic draw. I kept the original starter and battery sensor as spares seeing how they were not the problem.

In the past I had the 8.4 Uconnect radio delaminate and I replaced it with one from Amazon. Ran that radio for a year before these issues started without any issues. I bought another 8.4 Uconnect thinking that it was the problem but the same problems exist after replacing it a second time so now I have a spare radio too.

I also replaced the ABS HCU about a year ago with whatever part number superseded the original.

Other issues I have experienced are my compass reading completely off course as well as the ambient temp was sometimes dramatically wrong. I replaced the module in the overhead panel that I thought controlled the compass but it did not help but a new ambient temp sensor seems to have fixed that issue.

Other than what I have mentioned the truck has no mods or replaced parts. I have opened the TIPM and seed no signs of damage or corrosion but I cleaned it all thoroughly and put it back together. I see no visible signs of bad wires and I am now thinking that the BCM has to be the problem. I found this forum and figured that I would see if anyone here has experienced anything similar. I have searched everywhere and can not find another documented problem like mine. Everything related to "Battery Saver Mode" talks about the intake heater on the Cummings so I get no help there.

I have a OBDLink EX cable coming for my laptop as well as the Chrysler FCA Authorization Gateway Security Bypass Cable and plan on getting AlfaOBD as soon as the others arrive. Ordering a new BCM tomorrow unless I get some solid info from you all here.


Any help at all would be greatly appreciated.

I have a 2018 3500 Laramie, There is a recall on the HCu units you can get your money back for that , I got notice February 9 still waiting for part to be released. Mine started malfunctioning in October last year didn’t want to spend the $1800 for the repair. So I wrote NBST, must not have been the only complaint got notice of recall in December and I would receive written notice feb 9 which I got. Now my coolant sensor appears to be out .

 

[OtterlyFoolish]

I have a 2018 3500 Laramie, There is a recall on the HCu units you can get your money back for that , I got notice February 9 still waiting for part to be released. Mine started malfunctioning in October last year didn’t want to spend the $1800 for the repair. So I wrote NBST, must not have been the only complaint got notice of recall in December and I would receive written notice feb 9 which I got. Now my coolant sensor appears to be out .

My HCU was out defective for over a year before I was able to find a replacement unit in stock. I changed it out myself so I doubt that they would give me anything back. I did buy it from a Mopar dealer and do have the old one laying around for proof but I do not think it is worth the hassle.

 

[OtterlyFoolish]

No problem! That I am unsure of as I don't have a SGM in my 2014, but I think I heard the connection is under the steering wheel somewhere (for the star connector type bypass). There should be a lot of thread on here though explaining it.

I will re-emphasize make sure to make a backup of the BCM before doing anything. So many people skip this step and while it's not the end of the world you will save yourself a lot of time (and possibly money) by having a known-good config.

I will double check the location before tearing the dash apart and follow your instructions as close as I can and definitely ask if I get stumped.