The push button transmission shifter in my Regency will not power up. Additionally it won't let my coach start up, most of the time. Occasionally it does allow it to start but it still won't light up and the "Do Not Shift" light on the dash is constantly on.

I pulled the VIM out and checked out all the fuses, relays and board traces. The box checks out okay. The two power feeds to the ECU has proper voltage and the two grounds test out as well. From what I can find on the net this is a rather common problem.

My real problem is that the ECU is an Allison WTEC II and they do not manufacture that model anymore. Also the shifter panel is directly attached to the ECU so I am not certain that there is not also something wrong with it also.

Does anyone have any good leads as to who could rebuild this or who may have a reasonably priced re-manufactured unit that I could purchase? I did find a site on the net who can rebuild it for around 500 dollars. I think I got the link to them from this website (Barthmobile.com).

One other problem I have been experience lately is that the speedometer will fluctuate for a while and then peg out while standing still and idling. I have been told by the technicians I have contacted that these two problems could be related since the speedometer feed comes from the ECU.

Any additional information would be greatly appreciated. My transmission is an Allison MD3060.

I didn't see on its website that they do that sort of thing, but call http://www.autoxpresstech.com/ and see if they do it or know who can.

I had the instrument panel on my Lexus done by them - excellent service, more than competitive price.

I hope you are not running into an acronym problem.

With the advent of computerized engines the ECU became the electronic control unit the may be two parts.

You now have a TCM (transmission control module) and an ECM (engine control module).

Anyway good luck in you hunt.

BTW there is one for sale on ebay

I had the same problem with mine, and it was the neutral start relay inside the Allison black box in your electrical compartment. I bypassed the relay with a jumper wire and everything works just fine and Allison said it is not a nessesary relay as this transmission automaticaly goes into neurtal when shut off. Allison also sent me a new relay to install.
Good luck,
Darrell Moore

My coach has a VIM (Vehicle Integration Module) and ECU (Engine Control Unit). There is also a push button shifter which is mounted directly on top of the ECU.

I had pulled the VIM and checked out all parts. There are two fuses and six relays. All of them checked out so I also tested all board traces and all were okay. That was unfortunate since either fuses or relays are the problem in the vast majority of cases.

I sent my ECU to someone who repairs them and I received it back today. I cost $543.00 including shipping. It should be back in my coach sometime next week and I will update this posting.

There were a few bad components. The connector had also cracked and it was replaced (not an easy job at all). If all checks out okay I will post an update including the full contact information for this company.

quote:

Allison MD3060 Transmission

Yeah, the newer trans, with push-button-controlled electronics, has advantages and DISadvantages over my old 545 slushbox

on our big truck we had a similar problem, stuck in 10th gear (of 18). The readouts pointed to a bad ECU on the automated Eaton transmission. A new one was installed (hey they cost only $3100 plus labor) to find out it was a bad wiring harness afterall. Just a thought.

I need to ask a question about my Allison 4 speed.

I had it out for a drive two days in a row.
Both days it ran smooth no problems of any kind with the exception when I back it in the driveway. As I give it power to back up, it hesitates in reverse and then seems to surge backward. The problem seems to be coming from the
the reverse selection.
The shift selector is located on the dash.

Any ideas????? Is it safe to drive?

Jim

1985 Barth Regency
DD 225hp Ally Trans

I am definitely not a transmission expert but I'm certain that when others read this they will respond. I have found out that Allison transmission company may be able to answer some of your questions. A few months back I called them about a transmission temperature problem and they helped me out, even to the point at telling me exactly where the components on the transmission are. My experience with some of the Detroit Diesel service centers have been of help.

I hope this is not a significant problem for you.

quote:

Originally posted by Lance Walton:
If all checks out okay I will post an update including the full contact information for this company.

I was working on a mid 90's firetruck today and had to diagnose a shifting problem I Googled and hit search and came up with this post. After calling up Lance he sent me the following schematics. They were very helpful and I wanted to link them in this post for future reference. Here is his email to me

quote:

Here is what I have on the transmission, ECU, shifter and my latest schematics. Keep in mind that the two schematics are “living” documents. I seem to find something to add, delete or change constantly. I would put it in the mid 90 percent range of accuracy.

Transmission MD3060 & shifter Info


(2,153 KB) 3000/4000 Operator's Manual

MD3060 WTEC II Electronic Controls Troubleshooting Manual Removed by request of copyright holder

(2,143 KB) Newest Shift Selector Operation And Code Manual

(651 KB) Older Shift Selector Operation And Code Manual

Lance's Living Documents - 3 Parts

1993_barth_dc_sh1.pdf

1993_barth_dc_sh2-1.pdf

1993_Barth_Wiring_Verified

Bill
Thanks for the links some rainy night I'll have to read thru them to see if I can figure out why my MD 3060 doesn't wan to shift when it is cool. I remember seeing it may be a RPM issue. It does seem to rev higher when cold by the time it brings up the air pressure. I want to use for hunting this fall and if it won't move when cold I may be sitting somewhere for a long, long time

I finally got a chance to test drive my coach with the repaired ECU and it performed perfectly. As far as I can tell he only works on ECU's. He does a great job and his price is very good. Here is the information on who repaired it.

Transmission Instruments
3634 Long Prairie Rd. Ste 108
Flower Mound, TX 75022
1-866-439-9779
Transmission Instruments

Thanks for the info Lance. I may also need this place in the future. I have a very early MD3060 and not many people have the required test connectors for this early model any more. I use the push buttons a lot particularly driving in the mountains so one day------.

The PO replace the control unit before I got the coach, why? I am not sure but at least thanks to you we have a place that may be able to repair our older units.

Glad to be of help. I have received a great deal of good information from this site am more than happy to contribute.

Thanks Lance this may come in useful as mine acts up!