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valleybusman
Top Member

USA
798 Posts

Posted - 07/20/2016 :  11:29:35 AM  Show Profile  Send valleybusman an AOL message  Reply with Quote
I have a 2004 RE 300 with a DT 466 . Awhile back the transmission would set a 35-00 code . When it does this the gear selector number will flas , check trans comes on and bus go to nuetral . Press neutral and put back in gear and it will clear and work again . Iused my Allison doc to retrieve the code . While I was sitting there the transmission shifted out of gear and check trans came on and drive number was flashing . I looked at my allison doc . It said bus was in gear but transmission was nvl . I am wondering if power issue or ECU ? We have had some issues with electrical ramping up really high . Would like some thoughts . Thanks

valleybusman
Top Member

USA
798 Posts

Posted - 07/21/2016 :  08:00:58 AM  Show Profile  Send valleybusman an AOL message  Reply with Quote
Anyone ?????
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torque
Advanced Member

Canada
358 Posts

Posted - 07/21/2016 :  10:34:14 AM  Show Profile  Reply with Quote
In Allison DOC you should have a pin out for the ECU check your power and grounds, if they are good then it would be the ECU at fault. Allison DOC should also have step by step troubleshooting, is so follow it.
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valleybusman
Top Member

USA
798 Posts

Posted - 07/21/2016 :  12:23:47 PM  Show Profile  Send valleybusman an AOL message  Reply with Quote
Thanks for the help !!! I will hook it back up and see what it will do
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torque
Advanced Member

Canada
358 Posts

Posted - 07/22/2016 :  06:45:07 AM  Show Profile  Reply with Quote
Just keep in mind, the code isn't set until power is restored, so check also for intermittent, corroded or loose connections. Also you could get someone to wiggle and pull on wires while Allison DOC is watched for changes. If you dont find anything with the wiring, do you have another unit to swap ECU's? So far all my problems have been in wiring, but some have had ECU problems.
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OxDiesel-Doc
Active Member

25 Posts

Posted - 08/02/2016 :  1:17:18 PM  Show Profile  Visit OxDiesel-Doc's Homepage  Reply with Quote
I had the same problem with one of my allisons it ended up being a bad Transmission Control Module (TCU) I cant elaborate further on the issue but thats what was causing those symptoms.
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Troy87
Senior Member

United States
52 Posts

Posted - 08/03/2016 :  04:36:45 AM  Show Profile  Reply with Quote
I agree with Doc, The TCU may have gotten wet, or just went bad
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valleybusman
Top Member

USA
798 Posts

Posted - 08/11/2016 :  12:38:18 PM  Show Profile  Send valleybusman an AOL message  Reply with Quote
Wanted to fill everybody in on what I found out . Decided to take the bus for a run and create codes . Left the yard and poof transmission indicater went dead . Costed to the side of the road . No modes lights nothing . Shut bus down went back to shop to grab some tools and my laptop . Tried disconnecting the batteries .Nothing still . I hooked up my laptop and used my Allison Doc . Couldn't get it to read transmission . So as I am sitting there I decide to check the engine .fired up service maxx . Guess what . Nothing there either . so I open the batteries and find a blown fuse in the red wire off the batteries . I change it out . Another fuse . Pop so nwo I know this is a wiring probelm to everything . Try to start bus and nothing . I use a jumper wire to get bus back to shop . I found the main wire had rubbed thru another wire . Replaced fuse fixed wire and now my transmission problems went away . Thanks for the help guys
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