Cummings motor allison trans. Need help please

[vandeusen]

• i boiught a 1994 dynasty 38ft diesel last week. The automatic steps didnt work so we unbolted and ziptied to get me where i have to go. Arrived to my destination (34miles) upon arrival, i started to make a right turn into the rv spot when it died. after a couple of attempts i got it going and parked. The next day i cant do anything so i could use some advise.. Here is what i notice and did...
  
  the dashboard says DO NOT SHIFT. It is the ONLY light on dashboard. Trans. keypad is blank. Sometimes the coach will start and sometimes it actrs like i dont even have batteries connected. Sometimes she WILL go into D and sometimes (more then not) WONT DO ANYTHING.
  
  I checked the battery (11mo old) it was 12.59V and checked with alternator running and got 13.6V and the house batteries are just fine. Checked the ignition and replaced ignition selinoid but made no difference. Opened the allison transmission black box where the 2 fuese are and the breakers and everything looks good there. Played with ignition everything looked ok there too. Verified the chasis ground is good and not corroded. went underneath the tranny control shift and unplugged and plugged both gangs. Tested with the coach plugged into AC and also with it by itself DC and even with and without the inverter system being on..
  
  So, any ideas? And I have tach. when she starts, she runs great but its this DO NOT SHIFT problem im having.. Any help would sure be nice. Thank you

 

[RKins]

Where is your tranny shifter. I would disconnect the 2 big connectors going into that and check for dirty contacts and then re-insert.
If that doesn't help, you might want to gather up some info, like the model of the tranny (plate on street side of tranny), the info on the shifter and contact John at Transmission Instruments - real smart guys there and all they do is repair the shifter/TCU. I sent my shifter/TCU to them, they rebuilt and it came back looking/operating brand new.

 

[vandeusen]

Thank you I saw John's name in other posts but I wasn't sure if I was quite there yet and needing a TCU or ECU I guess I will give him a call today thank you

 

[RKins]

They are good people to just talk a problem through - they are great at diagnosing over the phone. I was having an inverted Pac Brake activation problem. I spent an hour on the phone with John over a few calls and jogged his memory that there was a special version of the Vehicle Interface Module (VIM) used in 94-96 that was wired backwards or at least differently than usual and it ended up that mine was wired that way. He emailed me the special notes from Allison on the WTEC II/VIM wiring. . We changed the wiring and it started working.
If you send your shifter in, like I did initially and there is nothing wrong, there is no charge 'cept shipping. Later on my push buttons were very hard to get the shifter to change gear manually - that's when they rebuilt it.

 

[vandeusen]

They are good people to just talk a problem through - they are great at diagnosing over the phone. I was having an inverted Pac Brake activation problem. I spent an hour on the phone with John over a few calls and jogged his memory that there was a special version of the Vehicle Interface Module (VIM) used in 94-96 that was wired backwards or at least differently than usual and it ended up that mine was wired that way. He emailed me the special notes from Allison on the WTEC II/VIM wiring. . We changed the wiring and it started working.
If you send your shifter in, like I did initially and there is nothing wrong, there is no charge 'cept shipping. Later on my push buttons were very hard to get the shifter to change gear manually - that's when they rebuilt it.

I finally got a call back and John is on vacation after talking with the person on the phone I decided to just to go ahead and ship it to them easy to take out $15 to ship it worst case scenario $55 is what they charge if nothing is wrong with it but him and I both think that this is my problem I will keep everyone updated

 

[RKins]

I finally got a call back and John is on vacation after talking with the person on the phone I decided to just to go ahead and ship it to them easy to take out $15 to ship it worst case scenario $55 is what they charge if nothing is wrong with it but him and I both think that this is my problem I will keep everyone updated

$55 - that's a new charge. Does it include return shipping?

 

[vandeusen]

55 if tget find nothing wrong with unit. 595.00 if they do. 595 includes return ship. It gets del. Totem today so fingers crossed

 

[RKins]

So that $55 is a new charge - it was free when I sent mine in. I bet since their name has been spread around they are real busy.
They are good at what they do. They repaired my TCU - I forget what I paid and then to replace the upper portion (where you push the shifting buttons) was a few hundred more. Like brand new now. You'll be happy.

 

[vandeusen]

I did get a call from them yesterday evening and they informed me that indeed my TCU was bad they're going to fix it and shipping back

 

[vandeusen]

Quick question guys I sent the TCU out to get rebuilt in the meantime while I'm waiting I decided to turn the key to see what would happen and the motorhome did not start at all it acted like there was no battery on the 1994 Dynasty is that normal? And while the TCU is out being repaired would that also cause the chassis batteries not to take a charge? Thank you

 

[RKins]

Quick question guys I sent the TCU out to get rebuilt in the meantime while I'm waiting I decided to turn the key to see what would happen and the motorhome did not start at all it acted like there was no battery on the 1994 Dynasty is that normal? And while the TCU is out being repaired would that also cause the chassis batteries not to take a charge? Thank you

No idea on those questions - never tried that.

 

[vandeusen]

So I got the TCU back put it in and sure enough that was the problem thank you

 

[vandeusen]

Took it out on a test drive after putting the TCU in ran perfect more power than I needed

 

[RKins]

Glad you're able to enjoy her now.

 

[wildebill308]

Took it out on a test drive after putting the TCU in ran perfect more power than I needed

That is a statement you don't often hear with RVs.

 

[Rich W.]

I just read this for the first time from the beginning. Great story - always nice when things work out like this.

 

[vandeusen]

Thanks guys

 

[Roadglide117]

Quick question guys I sent the TCU out to get rebuilt in the meantime while I'm waiting I decided to turn the key to see what would happen and the motorhome did not start at all it acted like there was no battery on the 1994 Dynasty is that normal? And while the TCU is out being repaired would that also cause the chassis batteries not to take a charge? Thank you

I believe with no TCU it does not talk to the neutral safety switch, it will not start if the TCU pulled out

 

[Wemustrv]

Awesome glad your are up and running!