Skip to main content ↑ ↓
Topic: Transmission wiring question (Read 851 times) previous topic - next topic

Transmission wiring question

I have a Allison 4000 transmission that is not sending some info to my VMSpc. Talked with Roger and he did some troubleshooting and determined no info is being sent. Can someone point me to where the brain of transmission so I can try to clean the connections as a place to start. I get the transmission temp but no retarder temp, gear indication, economy indication. Just would like everything to work if possible. Haven't had a chance to go to talk to an Allison shop yet. Hope it is something I can fix so my wallet won't suffer. My coach budget has taken a beating this year.

Thanks
Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Transmission wiring question

Reply #1 –
Keith,

  If you look first in the basement mounted on the wall or ceiling behind the HWH compressor. If not there then it should be behind the kick panel that runs from the steering column over to the drivers side wall.  If hid here it will be mounted on the drivers side wall framing. 

Here is a good pic. that George took as to where the ECU is if mounted in the basement and what you are looking for.
Flickering display on Allison shift pad

Here is a link to a pic if it is hid under the dash like ours is.
No crank, no start: 1995 M-11 in Plainview TX

Sometime in the '99/20 time frame is when they moved location so it will be like hunting Easter eggs.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Transmission wiring question

Reply #2 –
Mine is in the wet bay above the water pump!
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: Transmission wiring question

Reply #3 –
I found it, in the bay with the 12v compressor on the wall. Now I just need some time to take it apart and clean the connections.

Thanks
Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Transmission wiring question

Reply #4 –
Quote from: hdff –
Now I just need some time to take it apart and clean the connections.
I will be very surprised if you find any corrosion problem on the pins.  The connectors are VERY tightly sealed.  In the two posts linked below, you'll see photos of our Allison ECU and the wiring harness connectors, taken when I had ours out for a rebuild.  Yours should be similar.

No start, with Allison "snake eyes" (Problem Solved)

No start, with Allison "snake eyes" (Problem Solved)
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Transmission wiring question

Reply #5 –
Well if those are clean, and yes they are tight, any suggestions? I guess it's not really hurting anything but I'm kinda anal and like to have things working if they should...  those 2 ?? on the VMSpc for the gear selection just stare at me going down the road.....


Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Transmission wiring question

Reply #6 –
Quote from: hdff –
Well if those are clean, and yes they are tight, any suggestions? I guess it's not really hurting anything but I'm kinda anal and like to have things working if they should...  those 2 ?? on the VMSpc for the gear selection just stare at me going down the road.....


Keith
Maybe call Allison and see if there is a re-boot feature.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Transmission wiring question

Reply #7 –
Pins seem to get surface corrosion.  The instrument guy said work the plug ten times
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Transmission wiring question

Reply #8 –
Quote from: Caflashbob –
Pins seem to get surface corrosion.  The instrument guy said work the plug ten times

Keep in mind coatings on pins on electronics are rated for a finite number of "wipes".  Don't practice this method as "routine maintenance" or you will wear through the plating.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Transmission wiring question

Reply #9 –
Don't know if he is familiar with this issue, but John is in Flower Mound, TX and is the guru on shift pads and Allison ECU's:

Transmission Instruments
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Transmission wiring question

Reply #10 –
John is the one who recommended the multiple plug ins to me for my 97
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Transmission wiring question

Reply #11 –
Talked to John, he was no help for my problem


Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.
 

Re: Transmission wiring question

Reply #12 –
Guess Stewart and Stevenson, the Allison dealer up on I 10 just inside 610 on the east side of Houston is the next contact.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020