ATEC "do not shift" light

[ArtGill]

I have a 6V92TA, DDEC II with a Allison ATEC ytransmission in a NJT model 20.   I took the coach out to fuel up and stretch it's legs.  When I got back to my parking lot and went to shift to reverse the light changed on the touch pad but the transmission never engaged.  I tried to return drive and had the same result.  I shut down the engine because in the past I had been able to turn the power on the dash off and on and ATEC would reset.  But this time the engine would not crank.  I turned master battery switch off and pulled the fuses for the DDEC.  When I powered everything back up the engine would start but the "check trans" light and the "do not shift" lights stayed on.

I found the ATEC control box and unplugged and replugged the cables on the box.  Removed the ground wire, sanded the surfaces and reconnected the ground.  Would my TPS box cause these symptoms?   My TPS box got very wet so I took it apart and cleaned the board, but one of the contacts in the plug looks very dark.  If the TPS could be the problem, I can build a new circuit and replace the plug.

I'm going to try my DD dealer in the morning, but they are 40+ miles away.  Also I have reservations for a rally in Myrtle Beach for Friday, so I'm looking for a miracle.

Any and all suggestion will be appreciated.

Art
Morehead City, NC

[trailblazer2]

 Art;
Try taking the battery cables completly off the battteries,and leaving them off overnite. Ground the negatives to a good ground on the chassis. Sometimes this will work,it did for me.Make sure the gound is disconnected first ,and put back last. If this does'nt work,I think I have a manual on this tranny somewhere. I hope you can come to Genes Bus Rally the 29-30 of May In Fayetteville,NC!
Bill

[NJT5047]

There's another "ATEC" thread running regarding a DDEC 1 and ATEC fault.  Check that thread for Pete/RTS' posts.  He may be of assistance.  He's got the data for ATEC/DDEC II transmissions.
First thing to do is read the codes. 
The ATEC ECM has codes stored.   My guess is you have codes in the DDEC ECM also due to the failure to start.   
When you state that the 'engine would not crank'...are you referring to turning over, or cranking over but not lighting up?  If it wouldn't turn over, you've got battery/leads issues. 
Cannot offer much on an Eagle, but reading the DDEC/ATEC codes will give you some direction.   If both units are having intermittant problems, I'd start at the 12V power feeds for those units.  Check for bad circuit breakers or fuse cases. 
Good luck, JR

[Jerry32]

I had a problem like that once and it was the throttle position sensor or sw wasn't insicating the throttle at idle. Jerry

[Kwajdiver]

I had to replace that same sensor, that was the code I was getting.  Really don't think that was the problem.

You are chasing your tail, until you read the codes.  Do you have a flashing red light, near the ECM.  Maybe a switch, that will start it blinking.  If you do, and it startes blinking, decode what it is saying,, something like morse code.  If I remember correctly, (50-50) the TPS (throttle position sensor) code is 21.  (Warning, don't take my word for that.)  If you indeed have a code, post it, someone here will be able to steer you in the correct direction.

Good luck, this can drive you crazy.  My problem ended up, being two bad wires, bring the ATC and my shift pad.

Bill
back in Tampa Bay

[ArtGill]

I have tried to get the error codes, but have received none.  But in hindsight, I may not have tried with the switch on.   

Today I went to the lot to disconnect the positive battery cable.  So, I started the coach and the transmission shifted as it should.  No check lights.  Tomorrow I'm taking the coach to DD Dealer to see if they can read any codes. 

Thanks for all the suggestions.

Art

[NJT5047]

Bill, you are correct.  The TPS code is '21'..and '22'...
Art, if you have a Vanner equalizer (most NJTs do) disconnect the negative leads first. 
The vanner apparently doesn't like having the hot leads disconnected first. 
Since the vanner is always 'hot'...even the master disconnect doesn't disconnect the equalizer.
Not sure about a DDEC II, but you may have two CELs...one red and one green.  If so, the green light is the ATEC, and the red light is the DDEC ECM.   
DD will have a code reader that makes flashing out codes 'old school'...post what you find. 
The fact that you 'resolved' (however temporary) your problem while working in the battery compartment is a sign.  You've probably got a bad connection in the 12V tap, or maybe a faulty ground.   

JR

[NJT 5573]

Art,

Your 20 has the ability to display the codes for you using the yellow lite on the dash. Just power up and after the lites go out hold the check switch down and out come the flashes. 3 flashes and 2 flashes is 32, write them all down. Down on the switch for trans codes, (Yellow), up for engine codes, (Red).

Once you have the codes stored in pencil, start the engine and clear the codes. Hold the check switch down and push N,R,N and they are gone.

The big question is if they stay gone or reset. If they reset, then tell me what code resets and I can tell you what the book says to do to fix it.

If my 20 sits it likes to throw hickups. Hickups are codes that don't really exhist. Once you clear them, they usually stay gone for some time, although my ATEC is fond of throwing a 32 code about once a thousand miles.

The only time my ATEC would not bring me home, I spilled liquid in the shift selector and had to replace it for a couple hundred. Now I keep a sandwich bag around it.

[ArtGill]

I think I may have it fixed, Maybe.  Tuesday AM I visited my Detroit Dealer after blocking all the north bound traffic on US 17 because I could complete a U turn and when I went to backup my shifting quit again.  After a couple of power cycles it came back and I got off the highway and to the dealer. 

His reader showed the wrong number of counts when I moved the TPS.  We unplugged the three wire connector to the TPS interface box.  Everything seemed to work with the box unplugged except I had a "check trans" light.  He advised that it should be alright except the downshifting would be hard or not at all.  Well I got home and went to back in and no shift and no "check trans" light.  I plugged the TPS interface back in and backed into my parking space.

I took the TPS interface box a part and found that the water had  damaged the circuit board and the wire connections to the circuit board.  I made a new circuit and wires, sealed and supported with hot glue into the box.  Replaced the three wire plug with a four pin, flat trailer light plugs.  Test drive and everything works excellent.

That little TPS interface box has a lot of effects on both engine and transmission.

Thanks everyone for your suggestions.

Art

[Kwajdiver]

Yea! Not only did you correct the problem...   You made it better 

That TPS can be a pain sometimes.

Glad you got it beat...

Bill
Raining in Tampa Bay