| Author |
Message |
Joe (Frtnkr)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 29, 2006 - 8:00 pm: | |
I am having a new engine/transmission package put in my 1987 Flx Metro. The engine is a factory rebuilt 6V71, and the transmission has about 100K and was running when the transit garage attached it to the engine in 2000. It sat in their garage until I bought it this winter.
The garage I am using is among the best in my area and has been great to work with all along, however they don't see many automatic transmissions, mostly manual semi-truck transmissions.
The engine package is installed and the engine runs great but they are unable to get power to the control console left of the driver's seat. They spent the whole day today trouble shooting the transmission and got nowhere. They talked to the local Detroit/Allison shop as well as the transit garage where the bus came from and still got nowhere.
In order to remove the old transmission (it was running when I drove it into the shop) they had to cut the transmission wires because the harness would not come off. I got another harness from Nimco Bus and my garage installed it. They are getting power at that plug/harness but not at the control box.
All relays were tested an some where replaced with those ones we knew worked from the other engine package.
The transmission idiot light on the dash is on.
The control console is simply not responding...
Any ideas fellers? I gave them the transmission manual that came with the bus, I have looked in the archives here, and can't find anything. I just know this has to be something stupid and silly, but have no experience trouble shooting something like this, and the mechanics at the garage are coming up short too, so, from all those who know, at least something, let me have it.
Thanks in advance...Joe |
Greg Peterson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 29, 2006 - 9:03 pm: | |
If the check transmission light is on there probably is some fatal error that the V731 computer has detected and will keep the tranny in limp mode or neutral.
You need to do two things. First read out the error code number and then trouble shoot what it is telling you.
How do you do it? Some vehicles have a tranny diagnosis switch that will make the computer flash the idiot light code in order to tell you the error number. A better way is to connect an Allison diagnostic tool to the computer and read out the codes. This is the best way especially if you have more than one fault code.
Next thing you need is the computer manual from Allison (about $80) in order to understand what the fault codes mean.
Did you replace a DDEC 6v-71 with a mechanical 6v-71? If you did the computer will wonder what happened to the data bus and will freak out. You will need to change a flag in one of the computer variables in order to make it happy with no DDEC and add a throttle position sensor. (Did you add one?) This will probably take an Allison distributor to do the reprogram trick and it will cost $$$.
This is not any easy thing to diagnosis with out the above tools. Even with these most non-electrical mechanics will have a tough time with it? If you can find an Electrical Engineer friend to help it wouldn’t hurt either.
Good luck and be careful they could really run up the service hours with this problem. |
Joe (Frtnkr)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 29, 2006 - 9:18 pm: | |
Both engines are mechanical. Thanks very much Greg, for the info. |
Sammy (Sammy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 29, 2006 - 9:26 pm: | |
Joe, Does your engine have DDEC? (computer controlled)
The "control console" that you mention, is that the electronic trans shift selector?
What type of selector do you have - a pad type or does it have a handle?
Might be able to help you.
Sammy
(Message edited by Sammy on June 29, 2006) |
Joe (Frtnkr)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 29, 2006 - 9:58 pm: | |
No, my engine is mechanical, the control cosole is the trans shift selector, and it is a pad with N, D, 2, 3, R and DO NOT SHIFT. Hope that helps... |
Bill Gerrie (Bill_gerrie)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 30, 2006 - 8:51 am: | |
Joe
If you want to send me your mailing address I can photocopy the wiring diagram for the V731 and send it to you next week. Bill |
Sammy (Sammy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 30, 2006 - 1:56 pm: | |
Joe, the shift pad is not lighting up - no power to it, is that correct? |
Sammy (Sammy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 30, 2006 - 2:06 pm: | |
Joe, here's a few checks you can make:
If you're supplying 12 volts to shift pad,check wire 225 - goes to term 12 on shift pad.It should be a "switched" 12v supply.
If you are supplying 24 volts to shift pad, check wire 235 - goes to term 2a on shift pad. this too should be a "switched"24v supply.
You will need a Throttle Position Sensor and cable assy.This converts the linear mechanical throttle movement to an electronic signal.
Hope this helps you. Send e-mail if you need more info.
Sammy |
Joe (Frtnkr)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 30, 2006 - 4:00 pm: | |
Sammy, There is no power to the shift pad, correct, it does not light up. I passed the info along to the mechanic. He says he would like to talk to you over the phone if you could give him 10min. Please let me know if you would be willing to do that. In the measn time he is checking what you mentioned above. You can email me at joe@lamarmurphy.com if you want. |
Pete/RTS Daytona (Pete_rtsdaytona)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 30, 2006 - 5:24 pm: | |
Joe
Here a link to the v731 ATEC box pinout - if that helps
http://f3.grp.yahoofs.com/v1/0JClRE49lZE3t0F_F-CZxCFvr5SJlqgmEC2eTAYBvQ5UZu4zUI-m685SL6PVr 75ZMSsgQVtdtfuZydR44mAUGe5pKpobqG0CRFQ/v731-harness.PDF
pete RTS/Daytona |
Joe (Frtnkr)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 30, 2006 - 10:07 pm: | |
Pete, I am getting a "Document Not Found" message when I click that link, could you check it? may be my computer though...
I should mention that the transmission that was just installed in the bus (and the one that is not talking to its shift pad) was joined with the engine that was just installed when I bought it from the transit garage. It is not the one I drove it into the shop with. I was not sure I made that clear in my first post. |
motorcoach1
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 01, 2006 - 12:45 am: | |
You may want to check this the EMC ( electronic Control Module ) when the wires were cut , maybe the battery's were hooked up and wiped out the VCO ( Voltage Control Oscillator ) in the EMC, this is like a voltage regulator that is only for the power within the EMC. The EMC is the brain between the engine and the Tran's And the Shift pad. Pete has the PIN outs on the web i can't seem to down load eather. the EMC will stay in Limp Mode till it gets the right command or signal that would be generated by oil press. and a few other things RPM, alternator. Voltage regulator, Fuel pressure... another note is that the ECM carries it's own low voltage source too and cutting the wires could result in static discharge that could wipe the E-prom ...hope this might resolve your problem |
Joe (Frtnkr)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 01, 2006 - 10:10 am: | |
There is a good chance that the batteries were hooked up when they cut the wires, I'll check with them asap. |
Joe (Frtnkr)
Posted From: 71.49.37.116
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 06, 2006 - 12:02 am: | |
neg battery cable was disconnected |