Allison Will not engage

[Litefoot]

I'm having some minor (I hope) problems with the coach.
First a couple of days ago about Tuesday this past week I fired up the
coach and after letting it run for awhile to bill up the air pressure
the tranny would not engage. It's a Cummins 325 Turbo, Allison MD 3060
6 speed. Push button shifter. Only code I can get is a 7-0 which by the book is sump pump temp too low.
Twice in the past few days it worked, but then this am no go, even
after warm up, SOS. I have looked online, checked the fluid at the
tranny, and the shifter, fluid is at bottom of hot safe range, good
according to the book. Checked the jacks, fluid for the jacks,
everything as far as I can tell is OK, Nothing that I can come up with
as to why it's acting up.

Thanks in advance for any info you may provide.
Bummed out.
Roy

 

[Allison Expert]

Re: Allison Will not engage

Hi Roy, The 7-0 is for the oil level. You need to push the two arrow keys again to get into the diagnostics and see if their are any codes. d1, than four numbers. Push the mode button to go to d2 and so on. It may sound stupid, but do you need to depress the foot brake or take the e-brake off in order to put it in gear. Its easy to forget about this sometimes. The other thing thats possible, is a connector on the trans may have come loose. What happens when you try to put it in Drive or Reverse? Does the shift pad show anything? Is this a two digit display or one digit display shift pad? Lets start their, and see what ya got....

 

[Litefoot]

Re: Allison Will not engage

It's a 2 digit display, D it flashes the D-N .......... R it flashes the R-N.
Normal, when it was working it showed D-1 for D and R-R for R...
Thanks for the input
Roy

 

[Litefoot]

Re: Allison Will not engage

A Big Thank You goes out to allisontec...
For your info, This is my first diesel motor home........
The longer I have it the more I learn...
I am embarrassed to say,
but proud to know that the Allison is find.
The problem was the OHS sensor,(Operator Head Space) the nut behind the wheel. I have put over 1600 miles on the motor home since I purchased it with no malfunctions. I hold a current Class A CDL License, have driven everything from a motorcycles to tractor trailers with no problems .Till now.
I was cranking the motor home but not moving the motor home therefore I did now release the Park Brake, that was why the Tranny would not engage. I really feel like an idiot but at least the Trans is fine.

allisontec here in the forum told me that I had to apply the Foot Brake and release the PARK Brake to get the tranny to engage.
Tried it this am, serveral times and all is well. Man!!! it's a really good feeling to know I don't have to go out and spend a ton of money on this. Someone could have really taken me to the cleaners.
The OHS (Operator Head Space) sensor has been replaced, the nut behind the wheel has been tighten.
THANKS allisontec, you made my day !!!
Roy
Man you live and learn...
If it wasn't for flashbacks I would not have any memory at all.
Roy

 

[Allison Expert]

Re: Allison Will not engage

No problem Roy, thats what I'm here for....Just glad you got it working. Any other problems let me know. And that goes for anybody that visits these forums....

 

[Norris]

Re: Allison Will not engage

Don't feel like the Lone Ranger Tonto !!!!!! I have been drivin an RV for years.(gas rigs) Bought my first Diesel rig in November of '09, thought I knew it all, But I couldn't get it to move when leaving the Dealers lot. Thought and thought about it and finally came to the decision that "they sold me a bad RV", man was I hot. I went in all cool and collected and said to the owner that there was a big problem with the coach. He asked what and I told him he just smiled and said it would be fixed immmediately.
He walked out with me to the coach and sat down in the drivers seat, reached up and pushed in the parking brake and off we went !!!!!
I was never as embaressed as that moment, he told me it happened all the time and that he bet I would never forget to release the parking brake again. He is absolutely correct, I haven't since then, of course it always helpful if your wife is there to remind you !!!!!LOL

 

[Norris]

Re: Allison Will not engage

:evil:

 

[H2H1]

Re: Allison Will not engage

that is why this is the best forum you can find. There are so many men and women on this forum who will do all they can you help a fellow RVer out. So glad that you got that nut tighten up and happy camping. :laugh:

 

[nifty9]

Re: Allison Will not engage

Have not had that problem . but hopefully some one has informed you with the pre trip inspections to do before you move the coach ? tug test! an air brake coarse would be very help full to any one that opperates a air brake vehical.Dave

 

[C Nash]

Re: Allison Will not engage

:question:

 

[bobt1422]

Re: Allison Will not engage

first let me start with thank you for anything you can do
our trans switch , pad has no lights and our computor reads no connection from the ecu what fuses or breaker or what should i look for thank you Bob

 

[Allison Expert]

Re: Allison Will not engage

Hi Bob, Well if the shift pad is not powering up, it could be a couple differant things. First start by checking all of your battery connections and make sure you have at least 12volts. Next, check all your connections to and from the engine and trans computers. Also check the connector at the shift pad itself. If the connections are all good and tight, with no loose wires, or caroded terminals, it could be either a bad shift pad or bad trans ECU. What model/brand coach, and engine and trans do you have?? Does the shift pad have a two digit display, or one digit display? Lets start with those few things, and go from their....