Won't start / won't shift

on my 94 am eagle the vim is to the right side of the steering column
the tcm is held on the keypad with 4 screws and there will be 2 harness connectors plugged into it, make sure they are locked in place there is a release tab on the conector if they come unplugged without pressing the lock tab reinstall and make sure you hear it click if it does no click get some silicone electeical grease and lube the seal (I had that problem once) but I think at some point Allison separated them I have seen the tcm in one of the compartments at the rear of the coach it will be an aluminum box abut 2-3 in thick and maybe 4-5 in square the tcm and should have the Allison logo on it. my vim has 3 or 4 fuses in it could be a problem also check the battery box for fuses will probably have fuses for the ism and sometimes have for the Allison. the tcm has to power up and see neutral for the stater to engage so jumping the starter will not let the trans to go into gear unless the tcm is powered up and showing the proper display

No "Park" on an Allison 3000/4000 and likely no steering lock on a DP.

Be in PARK.

Key in IGNITION.

Slide KEY, and while key pressed to towards START,

Jiggle the steering wheel left and right.

Battery voltage may be OK at the battery, but a poor or loose connection, bad IGNITION SOLENOID, etc can cause this.

And, if the Allison shift pad "wakes up" pretty easy to check for diagnostic codes.

While I believe in the KISS rule, I doubt batteries with less than say 10V would crank a ISM engine, BUT well worth checking. Also, the OP being able to jump the solenoid tells me he's better than most at trouble shooting things.

The fact that he's spent this much time trying to help a stranger plus this about himself "do all my house, car, rv and motorcycle repairs..." tells me the batteries are not the problem.

Jim....I think the HWH issue was a symptom of the problem, not the cause. You say everything is powering up, but you have to jump it to start. Check the starting batteries (separately) and if nothing pans out, take a look at the ignition switch. I think "Ivylog" is on the right track.

wolfe10 wrote:
"Snake eyes" on the Allison means there is really something wrong with the Allison. Most common cause is low voltage to it. Could be nothing more than a loose connection at the shift pad or ECU.

Exactly. Classic low voltage symptom usually brought on by dead battery or batteries. Makes electronics crazy.

Do not let the leveling problem lead you in the wrong direction as that does not explain the NO Start problem. Solve the lack of enough power in the starting circuit (Snake Eyes in the shift pad) and the shift pad will probably come to life and the engine will start without jumping the solenoid. The starting circuit is fairly simple, and if it only has partial voltage at the key it will be easier to trace.
I would put 12V to the key and see if the shift pad come to life and what happens when you turn it.

I believe if you hold down the mode button for 10 seconds it should clear all the DTC in the TCM. Be sure to write all the DTC down for the technician. I wouldn't go very far before taking it to a service center though.

"Snake eyes" on the Allison means there is really something wrong with the Allison. Most common cause is low voltage to it. Could be nothing more than a loose connection at the shift pad or ECU.