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Allison fault code

For quite a while now I have had intermittent retarder activation, But it has become much worse as of late. On a down grade I would have the retarder and a few minutes later on the next down grade. No retarder at all. 'most' of the time if I stopped and turned off the coach and restarted, The retarder would return to operation. But the restart is becoming less effective at returning retarder operation.  So I dug into my shift pad and found a code.

D1/45-23 Open circuit, H solenoid, (do not shift light)=NO.  Retarder allowed, differential lock inhibited.
 
The transmission shifts the same as it always has and the temps on the VMSpc show normal. Next time I move the coach (this weekend) I will clear that code and go for a drive before returning the coach to it's storage location.

I did call two Authorized Allison shops in Pasco, Washington and gave them the fault code and I'm awaiting a return call.

EDIT TO UPDATE: Another one of those cautionary tales. I downloaded the Troubleshooting manual for the 3xxx-4xxx series transmissions. But with WS6_Keith's post and a new post about checking oil level lead me to find that there are TWO manuals based on what ECM one has. MY 1998 has the WTECIII which has a tapered shape with three connectors.

In the end, code 45-23 under WTECII shows it will allow shifting and retarder activation. The same code under WTECIII stops retarder activation as the only action.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Allison fault code- From 'around the fire ring'

Reply #1 –
Maybe this is the wrong model, but according to this document, that code 45, sub code 23 indicates a solenoid D failure, and should result in a do not shift.  See page 5-43 for troubleshooting.  There's a big note:

NOTE: Intermittent connections or lack of battery-direct power and ground connections may cause this and other codes.

Maybe a grounding issue?

http://elibrarywcl.files.wordpress.com/2015/02/diagnosticcodes.pdf

I did find this thread as well - check out the 2nd reply:  Allison B500 Code 45-23, 24-23 | Retarder stuck on, off?
Keith
2003 U320 38' #6197

Re: Allison fault code- From 'around the fire ring'

Reply #2 –
Might have to replace that. Yet I'm not sure that would be it as when I shut down and restart, Everything 'usually' returns to normal. And the trouble shooting manual also shows this:
Active Indicator Clearing Procedure for 45xx codes:
• Power down
• Manual

So it looks like this code clears on power down (key off?) Yet I just pulled that 45-23 code by turning on the key and using the trans keypad after the coach sat for 24 hours. I bet a months pay that when the retarder doesn't work it will show:

Main Code / Subcode Description/  DO NOT SHIFT Light/  Inhibited Operation Description
  ^              ^                                    ^                                    ^
45              25                                NO                                Retarder operation inhibited
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Allison fault code- From 'around the fire ring'

Reply #3 –
Quote from: WS6_Keith –
Maybe this is the wrong model, but according to this document, that code 45, sub code 23 indicates a solenoid D failure, and should result in a do not shift.  See page 5-43 for troubleshooting.  There's a big note:

NOTE: Intermittent connections or lack of battery-direct power and ground connections may cause this and other codes.

Maybe a grounding issue?

http://elibrarywcl.files.wordpress.com/2015/02/diagnosticcodes.pdf

I did find this thread as well - check out the 2nd reply:  Allison B500 Code 45-23, 24-23 | Retarder stuck on, off?
Now I'm confused. The ECU in your link looks exactly like my ECU.  The troubleshooting manual I downloaded was this one:
Allison Transmission
MD/HD/B Series Transmissions
WTEC II Controls
(Pre-TransID and TID 1)
MD 3060/MD 3066/MD 3560(P)(R)
MD 3070PT
HD 4060/HD 4560(P)(R)
B 300/B 400/ B 500(P)(R)
Dated May 1998.

So I'm not even sure if it's valid or not. Sure is crazy trying to find the appropriate publication as many are very close as are many of the Allison systems.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Allison fault code

Reply #4 –
Quote from: bigdog –
So I'm not even sure if it's valid or not. Sure is crazy trying to find the appropriate publication as many are very close as are many of the Allison systems.

The manual I linked shows 2007, so it may not be correct for your 98, although you'd expect it to be correct for everything up to that year with those models of trans I'd think.  From the other posts I found, sounds like it's not too hard to test the solenoid at the ECM connector to determine if it is a wiring/connection issue or a solenoid issue.
Keith
2003 U320 38' #6197

Re: Allison fault code

Reply #5 –
So I took the coach to the storage location. Started it up. Cleared the Allison code and went for a drive and dumped the waste tanks. All was going well, retarder was retarding. UNTIL I pulled off the highway. No retarder.
After parking I pulled the codes again. It was the same one code d1, 45-23. Open H solenoid. And the Allison book shows this code does not prevent retarder activation.
 
So I grabbed a flashlight and a can of deoxit and went into the bay and pulled the connectors. Everything looked pristine. So sprayed everything with the deoxit. Let it dry and reconnected everything.
 
Pulled the panel next to the driver and pulled the joystick plug and sprayed it as well. The joystick and shift pad were replaced in 2016.

Next is replacing the relay. The FT manual shows R4 which I would think is in the kick panel at the co-pilots position? I certainly didn't see one in the bowl of spaghetti under the instrument panel.

Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Allison fault code

Reply #6 –
Quote from: bigdog –

Next is replacing the relay. The FT manual shows R4 which I would think is in the kick panel at the co-pilots position? I certainly didn't see one in the bowl of spaghetti under the instrument panel.

Mine is located behind kick panel ahead of left drivers console just in front of retarder joy stick, attached to wiring harness long enough to pull up and out.
Doug W.
96 36' U270 CSGI #4946
04 Toyota Tacoma 4x4
PNW

Re: Allison fault code

Reply #7 –
Quote from: Doug W. –
Mine is located behind kick panel ahead of left drivers console just in front of retarder joy stick, attached to wiring harness long enough to pull up and out.
Didn't see anything close to a relay in that area. I'll go back and look again in the AM with a better flashlight and a mirror to have a snoop.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Allison fault code

Reply #8 –
Quote from: bigdog –
. The FT manual shows R4 which I would think is in the kick panel at the co-pilots position?

On your coach that is where you will find it.

Mike
Pamela & Mike 97 U 320

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

Re: Allison fault code

Reply #9 –
Quote from: Pamela & Mike –
On your coach that is where you will find it.

Mike

Yep Mike! That where it be. It was actually the R3 relay. Pulled it and off to NAPA. treated the connector with deoxit then put it back in. I'm not going to pull the coach out of storage yet as we have another trip the first week of June. I'll test it then.

Now for the open H solenoid code issue. Still awaiting a call from the local Allison shop on that one.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr