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

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

August 16, 2015, 04:58:43 pm

Our first "No Start" incident - I figure we are due.

Better it happens now, in our driveway, than out in the middle of nowhere.

Coach has (for the almost 2 years we've owned it) always started the instant I turned the key. 100% reliable...until now. Last time the engine ran was one month ago (7-16-15), and everything was totally normal. Between then and now it has just been parked in our driveway, hooked up to 50 amp. I went out today, planning to make a exercise run/fuel stop. I unhooked from shore power, turned key to "ON", and then the problem occurred. Trans panel gear indicators showed blinking "snake eyes" accompanied by beeping noise. After about 15 seconds the beeping stopped, but "snake eyes" remained on panel. In this condition, turning key to "START" will not activate the starter. The engine compartment starter switch is also inoperative.

What I've looked at so far:

1. The Allison shift panel has power, because it lights up the "snake eyes" indicators. It won't do anything else (like display codes, for instance).

2. Battery voltage on both house and start sets are good (13.6 volts). The generator cranked normally and started...it is running now powering both air conditioners. The boost switch works properly, verified by Multimeter reading at batteries. I tried starting with boost "ON" and "OFF" - no start either way. I am confident "Low Voltage" is not my problem.

3. Main ignition solenoid (in dash) is functioning normally, verified by Multimeter and A/C fan operation. Everything that is supposed to be powered when key is in "ON" position works just like it should.

4. Reading on Forum says "snake eyes" on shift panel indicates a "communication" problem between transmission and Allison panel or ECU. I have done absolutely nothing to disturb the wiring anywhere around the Allison ECU or the transmission. I crawled under the coach and looked at all the trans connectors - they are undisturbed and fully seated. Nothing on the transmission looks "unusual" or different from the last time I was under there. The connectors on the Allison ECU under the dash are fully seated and have not ever been disturbed.

I can't figure out what the heck could have changed since the last time I started the engine!

ANY IDEAS?

Re: HELP! No start, with Allison "snake eyes".

Reply #1 – August 16, 2015, 05:18:34 pm

Intermittent same issue.

Trans guy at the cummins shop says to check power to the trans itself.

Re: HELP! No start, with Allison "snake eyes".

Reply #2 – August 16, 2015, 05:22:45 pm

Did you check the aux start solenoid in front of the passenger seat? Try jumpering it.

Re: HELP! No start, with Allison "snake eyes".

Reply #3 – August 16, 2015, 05:22:59 pm

I had it occur on our FT and it was the top post on the positive chassis battery cable. Cleaned all the connection started right up and I did 400 miles. Next morning nothing! Messed around and was able to determine that starter cable and the other cable that connected to top post were loose. Took a cooter pin cut half off and placed between the post and the cables. Problem solved. Ordered a new cable. But as of today still have not changed it as I am thinking about going to a military type connector.

Re: HELP! No start, with Allison "snake eyes".

Reply #4 – August 16, 2015, 05:32:19 pm

Unplug shift pad and plug back in. Locate the Allison computer ECU and unplug connectors. I guess battery grounds should be disconnected to be sure no power (including any solar) is feeding panel & ECU. In cold weather key pad has been known to act up and a warm hair dryer has helped. Maybe try warm hair dryer to evaporate any moisture?

Re: HELP! No start, with Allison "snake eyes".

Reply #5 – August 16, 2015, 05:57:15 pm

Yes, check voltage on the "out" side of both fuses to the Allison (likely under driver's side of dash on 1993). Check for ground. Check that both ECU gang plugs are in and have "clicked" as locked in place. Also check the connection at the shift pad.

If still snake eyes, call this guy in Ft Worth, TX area. He IS the guru on repair of Allison electronics.

Allison ECU and shift pad repair. 866 439 9779 John Kopalek

Transmission Instruments

Re: HELP! No start, with Allison "snake eyes".

Reply #6 – August 16, 2015, 06:44:43 pm

My shop guy said cats eyes were no power. Or a bad TCM or pad

Re: HELP! No start, with Allison "snake eyes".

Reply #7 – August 16, 2015, 06:52:12 pm

Thanks for the helpful comments. I will poke around some more tomorrow, and call the Guru suggested by Brett...pick his brain.

Re: HELP! No start, with Allison "snake eyes".

Reply #8 – August 16, 2015, 06:56:39 pm

If you can get it to come back alive-- sometimes waiting a day will make a difference, use the up/down arrows to check for diagnostic codes. That will help John diagnose the problem.

Re: HELP! No start, with Allison "snake eyes".

Reply #9 – August 16, 2015, 07:09:55 pm

Snake eyes is non communication between shift pad and ECM. Nothing will happen until they communicate. Probably a bad power supply in ECM but John can fix it. Try this, I know it sounds silly but worked for me. Point a hair dryer at the ECM for about 10 minutes and see if it starts.

Re: HELP! No start, with Allison "snake eyes".

Reply #10 – August 16, 2015, 09:03:25 pm

The transmission gives permission to crank to the engine?

Re: HELP! No start, with Allison "snake eyes".

Reply #11 – August 16, 2015, 10:11:23 pm

Yep

Re: HELP! No start, with Allison "snake eyes".

Reply #12 – August 16, 2015, 10:34:37 pm

Well, I have GOOD NEWS, and a question. First, the good news: the neutral indicators are back, and the coach cranks!

I must give credit to Barry & Cindy, and to Twig. Barry suggested trying a hair dryer (aimed at the shift pad), but I discounted his idea because he mentioned "cold weather", and it obviously isn't cold around here. But then Twig ALSO suggested a hair dryer, and specifically said "point it at the ECM". So after 2 votes for a hair dryer, I said "What the heck..." and took the DW's dryer out to the coach. Turned it on and pointed it at the ECU under the dash - only took about 5 minutes and the problem went away!

Possible theory about what happened:

I only did one thing different today from my normal starting routine. When the coach has been sitting in our driveway for a long period of time, I normally go out and start the engine with the interior of the coach at ambient temperature. Then, if it's hot inside, I turn on the A/C and cool it down gradually as we drive.

Today, on the other hand, I did it in reverse. It has been very hot here lately. I have been leaving some windows open on the coach to help ventilate it on hot days. Since the coach is warm inside even in the mornings, today I went out and turned the A/C on for several hours before I tried to start it. It was pretty chilly inside the coach when the problem occurred. Perhaps, rapidly cooling the warm, slightly moist air inside the coach caused some condensation to build up inside the ECU? It's only a guess...

At any rate, the dryer worked, and I THANK the Forum members for providing a solution. However, I am also concerned about this happening again, perhaps in more inopportune circumstances. Once the neutral indicators showed up, I pulled the codes stored in the shift pad. It only showed one code: D1 69 32. Barry's tech site decodes this to mean "SPI COMMUNICATIONS LINK FAULT IN ECU". So, is this problem likely to return, or do you suppose this was a freak occurrence?

Allison Transmission Codes Manual

Re: HELP! No start, with Allison "snake eyes".

Reply #13 – August 16, 2015, 10:53:55 pm

Well, you know how to get it going again anyhow. The old saying...."if it's going to fail, it's going to fail when you need it most." comes to mind. I sent mine to John few years ago and has never failed since. Cost ......about $600. Sleep at night.....priceless......you make the call.

Re: HELP! No start, with Allison "snake eyes".

Reply #14 – August 16, 2015, 11:41:55 pm

......and as an aside.......John rebuilds the ECM and the keypad together, so you would send him both.

Re: HELP! No start, with Allison "snake eyes".

Reply #15 – August 17, 2015, 09:09:43 am

Yes, diagnostic code 69-32 WILL reoccur. And this is one John is very familiar with fixing.

Re: HELP! No start, with Allison "snake eyes".

Reply #16 – August 17, 2015, 09:30:40 am

I have been doing some research this morning. First, I tried a Google search on the fault code 69-32 "SPI COMMUNICATIONS LINK FAULT IN ECU". I'm sorry to say that this is not a uncommon code in the Allison transmission world - the RV forums have many threads pertaining to this subject. Bottom line: 69-32 is the Kiss Of Death! Once you see this code stored in your shift pad, you are basically driving on borrowed time.

Following Brett's lead, I went to the Transmission Instruments website. Transmission Instruments
The owner and chief engineer, John Kopalek has carved out a nice niche business restoring the old Allison ECU and shift pads found on many classic RVs. His reputation appears to be golden, and he has 100% positive feedback on many RV forums. On his "trouble-shooting" page, the notation on fault code 69-32 is pretty clear: "Have You seen code 69-32 already? Stop troubleshooting = 100% defective ECU!!!"

So, the decision is made. The coach is safely parked in our driveway, and we have 4 weeks before our next scheduled trip. Plenty of time to get this problem permanently resolved. I will call John this morning and confirm the details, then pull the ECU (and probably the shift pad) and get them shipped off to the repair shop. As Twig says, the value of avoiding a untimely "dead in the water" situation is priceless. We (the owners of old RVs) are fortunate to still have skilled craftsmen around to work on our ancient hardware. Sadly, I foresee the time when this will not be true.

To finish this thread, I will report back when the ECU and shift pad restoration process is complete. Thanks again to those Forum members who consistently lead me out of the darkness and into the light.

Re: HELP! No start, with Allison "snake eyes".

Reply #17 – August 17, 2015, 10:00:02 am

Quote from: Chuck & Jeannie – August 17, 2015, 09:30:40 am

We (the owners of old RVs) are fortunate that there are still skilled craftsmen around to work on our ancient hardware.

Indeed!

Re: HELP! No start, with Allison "snake eyes".

Reply #18 – August 17, 2015, 10:17:40 am

Quote from: John/Pat – August 16, 2015, 05:22:59 pm

I had it occur on our FT and it was the top post on the positive chassis battery cable. Cleaned all the connection started right up and I did 400 miles. Next morning nothing! Messed around and was able to determine that starter cable and the other cable that connected to top post were loose. Took a cooter pin cut half off and placed between the post and the cables. Problem solved. Ordered a new cable. But as of today still have not changed it as I am thinking about going to a military type connector.

John

I had a similar issue last year and limped into MOT under de rated engine. Keith Risch found the same thing and changed all of my terminals to the military/marine type. He says they will not vibrate loose like the auto terminals do. Change them out- it is a cheap fix for a big problem.

Ted

Re: HELP! No start, with Allison "snake eyes".

Reply #19 – August 17, 2015, 10:24:56 am

Quote from: Ted & Karen – August 17, 2015, 10:17:40 am

Change them out- it is a cheap fix for a big problem.

Good advice. I did all of ours when we installed fresh coach batteries last year.

Amazon.com: NOCO TZKIT3 Lead-Free Military Grade Zinc Battery Terminal Kit:...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: HELP! No start, with Allison "snake eyes".

Reply #20 – August 17, 2015, 03:31:57 pm

Talked to john about my 32-12 codes and a rare set of snake eyes on my shift pad.

After sept 94 according to him Allison upgraded the ecm to prevent moisture from entering it.

His suggestion for my issue was to pull a chassis battery cable and then remove and reinsert the ten pin plug in between the pad and the ecm ten times

Contacts corrode after twenty years.

My guru agreed and has a Wurth contact cleaner he will use to both clean and lower the return of the corrosion in my case.

Re: HELP! No start, with Allison "snake eyes".

Reply #21 – August 17, 2015, 06:02:45 pm

Update. I just went out to the coach to check the status of my "glitch", and it is back. "Snake eyes" are back on the shifter display, and engine will not crank. Just reinforces my decision to get this problem fixed NOW. I would definitely not want to drive the coach any distance in this condition. I talked to John at Transmission Instruments this morning - he said no problem he has the cure. I will get the stuff mailed off tomorrow, and hope for the best.

Re: HELP! No start, with Allison "snake eyes".

Reply #22 – August 17, 2015, 07:42:38 pm

my brother had a problem where the shifter stopped working. We took the shifter and ECU to a local allison service center(Stewart&Stevison in Houston,TX) and they ran test on both of them and determined that the problem was the shifter. Great, easy fix, just one plug, but $2700. It was the problem. That was on a 93 U240, md3060.

Re: HELP! No start, with Allison "snake eyes".

Reply #23 – August 17, 2015, 08:19:04 pm

Shifter not working and snake eyes are separate issues but if it involved the keypad and ECM.....Transmission Instruments would have fixed it for a fraction of $2700.

Re: HELP! No start, with Allison "snake eyes".

Reply #24 – August 17, 2015, 09:09:42 pm

Every battery in our coach has heavy duty "military" type battery terminals, and if any terminal acts up in any way, we just replace it with spares. No need to change cables.

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