8 Speed Swap Diagram Help

[1500Teej]

I got the 8hp70 swapped in and I am sorting through the diagram that Russell from SGA posted here
View attachment 519745

I wired everything up following this diagram. When I try to start my truck it won’t start and my PRND lights are all illuminated yellow and the electronic shifter will illuminate P. Then intermittently my dash will show only P in the normal colors and bounce back between. When the push to start is in run without the truck running (it won’t crank) my rotary shifter shows P as well as my EVIC. I believe I either have my CAN C lines going to the wrong place. I wired them into the CAN C lines coming off the RF HUB. I think that’s the issue. Only other thing I can think of is I should wire the CAN C lines into the shifter instead of the RF HUB. But I don’t wanna start splicing electronics until I know where what goes and vice versa. Also the ignition pink/white wire, where does that wire into? Can someone whos down this guide me in the correct direction? Need my truck running before Monday morning

 

[Brandon-w]

Not to throw you off the trail but are you connected to a Lin bus or a can bus circuit. Some electronics that I've dealt with in these trucks are both, like the switching systems I've found to be Lin bus.

Could you not just easily test by running wires to your obd 2 port and seeing if it recognises the can readings before you splice anything further?

 

[1500Teej]

I believe if I was that smart I would probably have went that route when I started troubleshooting. So you’re saying run my data lines into with ports in the obd2 connector?
My evic is showing that the pcm doesn’t see the transmission is in park yet my rotary shifter shows only the P illuminated. I need to figure out where to tie my wires into so the pcm gets that signal from my tcm showing it’s it park like my shifter does.

I’ve been looking for the wiring diagram for the 6 speed transmission plug. Is it possible to find a data line there or atleast the wire that shows the transmission is in park.

 

[1500Teej]

Pics from the reading I’m getting from my transmission

 

[1500Teej]

I found this and wired into the CAN lines off the pcm. I no longer get that pcm and tcm no communicating error. It’s just my truck doesn’t think it’s in park… Yet it is in park. Intermittently all letters on the dash with go from yellow to just the P in silver illuminated.

 

[Brandon-w]

Stupid question but did you select the right shifter in alfaobd?

 

[1500Teej]

I checked. It said Autostick. I changed is to 4pos Rotary Eshifter PRND DS (RS4) still getting this in ACC

 

[Brandon-w]

That's pretty much out of my area of expertise. Do you have hp tuners? It's a long shot but you might be able to change your transmission to 8 speed in there and have everything acknowledge its a the 8 speed in there now... I don't know.

 

[smoothee]

Are you on FB? A lot more guys have done the swap on there and may be able to help out too (High Performance Rams, OnlyRams)

 

[1500Teej]

Thanks everyone for your help and responding. I’m gonna bite the bullet and borrow a car for work.

The route i’m leaning towards is maybe I need to swap the pcm/ecu from a 2013-2014 8 speed ram into my truck along with the correct 8 speed harness and that should fix it. I will look around. If any of you guys have either of these parts laying around your garage or storage area. I’m in the market. I personally think that early 4 gens bcm/ecu/pcm needs to be replace to newer units that come from the factory with the 8 speed options

 

[1500Teej]

Update.

I got a 2014 8 speed pcm from lkq. Then I went and got a new brake pedal sensor and voila my truck starts now!! Thanks everyone for your help. Now lol the next hurdle is I shift the rotary shifter from P into R/N/D and the selector moves but the illuminated light stays on park. I’m guessing I need to add more transmission fluid? Thoughts?

 

[1500Teej]

FIXED!!!

Thanks everyone.The bcm kept kicking back my gear selector in alfaobd, unknowingly. I disconnect the battery and made sure the truck lost all electrical charge i.e. pressing the brakes and various buttons and knobs. Went back, selected 4pos rotary prnd (rs4) & enabled all the tcm components disconnected. Waited about 10 minutes started the truck up and drove home. THANK YOU JESUS!!!!!!

 

[1500Teej]

Update!

So after about 2 days of driving my truck died on me. I started getting service electronic throttle errors and then my truck slowly over the next 2 days would start then idle like it’s about to shut off and I got no response from the pedal. I believe it was due to the pcm being from a wrecked truck or vin mismatch or something. So frustratingly I found other means of transportation. Over this 2 week period I ordered the 2013/2014 8 speed engine harness with the 8 speed transmission plug. I finally got around to installing it and my question is my old pcm that came with my truck still looks for the rfe transmission. I can’t change this in the pcm or atleast I don’t know how to. I changed it in the bcm but my truck still says not in park. Is there a way to change this or do I have to purchase a new pcm?

 

[Evguy1]

Have you got HP Tuners? Sounds like you need to change the PCM from 6 speed to 8 speed.

 

[1500Teej]

No I don’t have HP Tuners. I purchased another PCM and installed the 8 speed engine harness now I’m getting the codes P0513 & U11C2. Can’t start the truck due to a skim message & tcm message P0513 & U11C2.

 

[1500Teej]

Update.

I got everything working thru alfa obd (rewrote vin & installed the proper 8 speed harness connector that goes through the firewall passenger side)!!

Thanks everyone for your help.