RE: Allison Transmission Questions
Hi Allison Expert, (and others)
Great forum, I've learned a lot reading the older posts the last couple of days. My family and my wife's sister's family (seven of us and four dogs) are traveling cross country from Oregon to Florida. Right now we're stuck in the Dallas area.
We recently purchased a 1993 Gulfstream 2000 on a spartan frame with a Cummins and an Allison MD-3060 with push button selector. It has only 41k miles, so it seems to have sat quite a bit, and by the condition of the interior, it had been at least couple of years. The seller drove it to my location with no reported problems.
When I first drove it, it took a long time (15 min) for the "Do Not Shift" light to go off, even though we had over 110 lbs of pressure. The ECU behaved normally then. The second time I drove it, I went about 80 miles and the DNS light came on and off intermittently, while all the lights on the ECU blinked the whole drive.
The next morning, the ECU would come on, flash for few seconds, then go out. I had not yet downloaded the "Allison_WTEC2_Manual" so I did not have a chance to check for diagnostic codes, but in retrospect it seems like a code 66 33, a Central Operating Processor timeout, and the flashing lights seem like a power error. (Can't say as I remember where in the troubleshooting manual I read that last part.) We started it several times that day, and near the end of the day, it stopped coming on at all. Then we pulled it from the dash and it seemed very hot, even for Texas.
I then ran a voltmeter on pins B1, B2, B9, B11, and B18 of ECU connector B and got appropriate +12.8v and ground on those pins. The engine was off, of course- the engine wont start with the ECU pulled, but cranks right over with it in. With the ECU out, I'm not getting voltage from any of the other connectors.
With some finagling of park and regular brakes, the light DNS light went off for a while, but it wouldn't shift into gear.
I've yet to locate the fuse panel for the engine/transmission systems, but with the voltage coming in, it's seemed like a low priority, still looking though.
I don't have a Prolink-9000 to read diagnostic codes, and I am wondering if one of the modern readers would do the job. I'm not sure what databus to use to talk to a early 90's MD-3060, is it J1939? Also, the WTEC2 manual may not be the right one for me to referring to, it's copyright is 1998 (5-6 years later) and several pins referred to in the manual's diagrams are blocked ("reserved") and don't go anywhere. (Pins A5, A8, A9, A17, A22, A25, A26, A27, A33 and A34 on ECU plug A and B3, B4, B25, B26, B29, B30, and B34- not present).
So What do you think? I'm going with:
1. New operator error.
2. Bad fuse.
3. Bad ECU.
4. Frayed/shorted/broken wire to the ECU.
So right now I'm hoping for 1,2 or 4!
Please Help!
And thank for all the input!
Nick Frost
