Question. Mel and Diane who just left Q are at the border to come down to San Carlos to meet us and just called to say he has been having an issue with the shift pad in that he gets ibtermitten snake eyes but the coach jeeps going with no issues. They clear after a short time but has no idea what could be going on So I ask for ideas hoping they make it and we can help when here. Is there a service shop in Tucson.
Thx
Johnh
They are driving on borrowed time. Have them pull the codes from the Allison brain box. If they get code 69-32 the ECU is dying and they risk getting stuck with a no start situation (usually at the worst time).
https://www.foreforums.com/index.php?media/item/allison-error-codes-and-shift-selector-operation.942/
See link below for our story:
No start, with Allison "snake eyes" (Problem Solved) (https://www.foreforums.com/index.php?topic=25783)
Or, if time is a factor, go straight to the trouble shooting steps at the website linked below.
Transmission Instruments (https://www.transmissioninstruments.com)
John,
There are major Allison shops in Mexico that offer everything from repairs to exchange transmissions. One member had a failing transmission overhauled for $4400 complete when the cost in the States was much more than that. Might pay to do some investigation. I can't remember the name of the forum member with the bad trans.
Pierce
It may not be the same problem, but we had intermittant trouble with our 3060 while on the way from Iowa to AZ a couple of weeks ago ending with snake eyes and no start. Luckily, we had decided to stop at a campground and were stuck there rather than the side of the road or fuel stop, etc. I checked things over and used the troubleshooting tips that Chuck linked to up above. After talking with John at Transmission Instruments, I ended up removing the ECM and shift pad and sent them to him for rebuild.
There is no way I would cross the border and hope to make it to San Carlos with a known issue like this.
Unplug and replug the ECU and shift pad. Clean contacts with an electric cleaner.
Many have found that warming the ECU and shift pad with hair dryer on low and from a distance helps.
But, while I am a long-time Mexico traveler, I agree, I would not cross until more than the above temporary fix was accomplished to get me to a safe place.
ABSOLUTELY, DO CALL JOHN and have him walk them through the diagnostic process. This (repair of this generation of Allison shift pads and ECU's is what he has done for a living for many years: About (http://www.transmissioninstruments.com/about/)
Yes last night he called me from border and I gave him Johns number to call first thing this am. Told him not to try getting here while not knowing what is going on. He is supposed to call me soon and I will explain how to read codes but think John will have him doing that maybe. They are presently in Why with only phone and no internet, so may have to have them at least go back to Aho and stay but not sure if there is UPS there.
While at Q I believe they have done the unplugging and hair dryer job but he said on way to Lukeville it came back a couple of times. He has not had any issues like no start etc or it shifting while driving but I told him to find out from John what he thinks. Coming down a week or so late is a pain but better than stuck along the road. There is an Allison shop in Hermosillo but do not know if they are compertant on the electronics and this place was hard to find a few years ago and I know that city fairly well.
Thanks to all, and I will keep you informed.
JohnH
Yes on call John. A friend had the snake eyes a few weeks ago. We followed John's diagnostic advice, and sent the ECU and keypad to John. One week and under $300 and all is good.
I suspect calling a shop would have been a tow, $1000, a month of waiting, plus John's service and the shop markup.
I'm pretty sure if you go to any Allison shop with the snake eye problem they will only offer one solution: buy a new ECU.
So then it is just a question of money and time. Only the coach owner can make that call.
They can pay the going price ($$$$) for a new ECU from Allison, assuming the shop has one in stock. May be cheaper in Mexico?
OR, mail the ECU and touch pad to John's shop, wait (somewhere) for the round trip mailing time (variable), and pay the repair cost (variable).
Roland lives in Ajo. He might know about the UPS store and also possible places they could stay if they decide to send ECU to John?
https://www.foreforums.com/index.php?action=profile;u=1667
Thx Chuck. I know Aho and forgot there is a UPS at the Electronic store on Main St and we have stayed a few times on way down here at an RV Park called Belly Acres it is only $25a night and includes all services so will tell them to go there and wait while Ecu etc are mailed to John.
Would have thought Mell would have called by now to be honest
Johnh
John at TI fixed our ecm and shift pad and overnighted it back the same day he received it. It was $851 with the extra UPS charge. 2 year warranty.
I also paid a little bit extra when I sent it for morning delivery which may not have mattered.
Just talked to him and told him to go back to Ajo and park there and send box off. They visited Roland on way down so know his home.
Guess we will find out later today what is John's thought but Mel said he is going to send it to him regardless.
Thx
Johnh
Hi all,
Could someone post john's contact info in case of issues in the future?
Transmission Instruments (https://www.transmissioninstruments.com/)
Dumb question? What is the " snake eyes " problem and where does it show up?
It is on the shift pad display. I've seen it called snake eyes, cat eyes, chicken feet, and maybe more. For example, my WTECII display normally shows N N if in neutral. The snake eyes show up in place of the N's.
That's not what I have on my U225. I have a lever shifter; pretty sure it operates a cable.
Then you don't need to worry about Snake Eyes. Only affects Allison transmissions with electronic touchpad control.
As in many cases, more simple IS more better! :thumbsup:
Your transmission is just mechanical and doesn't have an ECM. You will never have electrical problems like snake eyes :)
Short update.
Roland has been emailing me and told me that Mel is bringing the parts to his house and they will package them and send off to John.
I still do not know if it threw any codes that are serious and have a sneaky feeling that as he had no driving issues or non starts that this could turn-out to be a bad electrical feed problem. He has had alternator etc issues last 6 months.
Does anyone know were the battery terminal block is on a 94 GV 240 as I want him to check condition of it while waiting for parts to come back
Johnh
Completely different (non-electronic) transmission.
What is the "battery terminal block"? Sounds like a common positive connection point for all the battery power circuits?
Don't have anything like that on our '93 U280. Closest thing I can think of would be the main 12 volt panel in our center storage bay (under the white fiberglass cover). All my 12 volt power circuits originate there.
Panel is depicted on my B-2126 Automotive Wiring Diagram. See photo below:
There are 3 big 90A circuit breakers across the top. Main 12V feed to dash (ignition solenoid + all fuses and relays) comes off top left 90A breaker.
(Ignore yellow arrow in photo)
There are TWO fuses that supply the Allison, at least on the 1993 U240. Pop the dash up and they are in front of the driver's side and labeled.
My recollection is one 5 amp and one 15 amp.
Yes Chuck. I had one on the 295 so thought all may have them.
Do you think like me that if the coach does not have start issue after snake eyes and drives as normal that a 12v feed issue will cause them and if it is a momentary issue they would go away then come back, which is what was happening from what I can remember when he last talked to me.
John
Sorry - above my knowledge level. Did he actually call John K. and ask
his opinion about the observed symptoms?
It would be REALLY nice if he pulled codes form the ECU before removing it. The codes would do more than anything else to point out the probable source of the snake eyes.
If the shift pad is showing snake eyes it can not display diagnostic codes.
Yes, is intermittent snake eyes you could check for codes when the display is normal.
Which is exactly what I was HOPING was done while the opportunity still presented itself.
The problem has been repeatedly reported as "intermittent" from the start of the thread two days ago.
No codes were pulled sadly enough, and he has talked with John and although John could not give him any direct answers they are sending them to him as we speak. Roland is helping.
Mel called from Roland's home and I told him to read all the posts put up.
So, thanks to all again as we have done all we can from a distance and will wait for any verdict. Rest assured I will write any and all answers(or non) once it is back.
Chuck, you are right as they were intermittent.
Johnh
John,
One thing about John K is he won't sell you a pig in a poke. If he checks out the unit and all is good he will tell you that your problem is elsewhere. As we say here in East Texas "he is good people"
Mike
If you read his web sight they go into really good trouble shooting procedures if followed would be help full. The special test light they describe how to build and would be beneficial to anyone that thinks this is within there trouble shooting skill set (and it is) should have prebuilt and stored away with their spare parts and tool kit. I'm going to make one up soon and a small box to prevent breaking the bulb. The big advantage of a bulb is that it requires some wattage too work were as a volt meter can be fooled and show voltage but drops under any load like the light bulb.
I think I told this story over a decade ago. Our previous FT would spontaneously show snake eyes. That is a problem. The bigger problem was when it came back on, it shifted to first gear. You might can imagine the jolt you get when you shift into first at 60MPH.
The problem was a failing component in the ECU. Had I found a parking place and sent the ECU to John, it would likely have been a few hundred dollars. Eventually, the board failed more dramatically and was beyond repair. We were LUCKY to pay only $1000 for a used ECU, and equally lucky to find it within about 100 miles of where our coach sat parked and disabled in the emergency lane.
Scott I made a test light out of an old headlight connection and it has paid off a
couple of times. The standard test light would work but a headlight bulb used to
much current to work.
They showed a 1156. Not today but on the list
This is mine, crude but effective.
Need to be able to probe the harness
Quote;
Assemble 12V/15-25W light bulb (spare brake lamp bulb or similar – #1156, #1073 etc.) with 20 gauge solid copper wire (ordinary hookup or "bell wire"). Strip 1/2″ on test side. When you check ECU connectors, the lamp must glow bright white light. A dim light will indicate a bad connection somewhere; likely due to oxidization. A voltmeter will not indicate bad connections. An ordinary voltmeter or VOM isn't reliable for this test. However you will need one to check the lower voltage systems.
Don't know if it has been said but there are a number of places if you use a test light you could burn up a circuit board.
I believe HWH has warning all over the place to do not use a test light for checking.
Yes I wouldn't use a sledge hammer to install a windshield either, but he is the man that repairs these units and has been kind enough to provide really good troubleshooting guidance. I personally would be comfortable using his information for that. This was only for that specificity and nothing to do with your HWH. DWMYH.
Scott
Yes John is known to be honest as it goes with the name, lol
I did read his info on website.
Johnh
Roland emailed me to say that they did the testing as mentioned on John's website and it showed that there was damage on the equipment, so in a way that is nice to know that the problem is most probably all in the units Sent to be repaired.
Johnh
Mel and I did the test and the light shined brightly. The repair shop should get the equipment today. In our haste to ship the units we neglected to ship overnight. Or maybe not as Mel is helping me with our bathroom remodel today. 😁
Roland
Roland, work him hard as he owes you!!!!!
John
I believe that the package arrived in Texas this morning so maybe it will be back in Ajo Wednesday. Here's hoping for them.
Johnh
Package was delivered at 10:45 this morning.
Roland
Well after a week the parts are back and NO issues where Found by John and I guess no codes thrown. Mel informs me he has put it back together but have not heard if it is working but assume it should. He feels confident it will get him down here Saturday, so hope it does. I am now back with the mindset that he has alternator/charging issues as it was replaced 2 yrs ago by a Delco Remy one but he told me the excite wire etc was not hooked up but it was working!!!
I will wait till he gets here and find the model then see, or get back to this group of experts to sort it out as he cannot go on this way.
My thought is that if the ecu sees low voltage it would show cats eyes, so does anyone have any knowledge of this to give me something to work on ?.
Johnh
Sorry, nothing here. AFAIK cat eyes means ECU is broken. If it's
not broken and still showing cat eyes, even if intermittently, then that's above my knowledge level.
But, as you say, it's certainly something that
must be straightened out, one way or the other, by someone.
If John said the ECU and shift pad check out, that really points to a connection/wiring issue.
Check pins CAREFULLY and look for any evidence of rodent damage to wires.
Mel started his coach this is morning after installing the Allison ICU. I checked the battery voltage on the dash and it indicated 12 volts. Turned the lights on bright and the voltage dropped a bit and did not rebound. Voltages was never above 12 volts. Measured the voltage at the batteries. House voltage was 13+ chassis voltage was just about 12 V maybe a bit more. I suppose we should have checked the chassis battery with the coach running but it was reading just about the same a the dash meter so we did not. Didn't think about it actually as Mel decided that he would drive down to Mexico with the boost switch turned on. He's got a solar panel powering that battery bank so I believe he will be OK. But that's just me. I drove our coach for six months with a bad alternator without getting stranded. Never at night naturally. Mel has a three to four hour drive with bright sunshine so they should be OK.
Roland
Roland, so have they left to drive down now, as was expecting them to come tomorrow
Johnh
Brett, when Mell installed the ICU he put both connectors on, of and on again eight times, he actually counted. He does have an at alternator issue for sure whether that is causing his snake eyes remains to be seen I suppose.
Roland
John, when I left they were getting ready to leave. I assume they left.
Roland
Pretty easy to diagnose an alternator/battery isolator issue if he has access to a digital voltmeter.
Obviously, first step is to verify that all connections on alternator and isolator are clean and tight. Pay particular attention to the small sense wire.
Let us know if we can help.
Wolfe, I have all tools and can test out just depends on what alternator he has as it looks like some of the Delco ones need their isolator which I am sure he has original. Roland's reply on the voltages has me curious as those are not good numbers. Test the alternator output at B for start and go from there.
Will be in touch I am sure, thx
Johnh
Roland, what time was that as need to know when to expect them.
John
John I left them around 9:45 this morning. I have no idea when they left. Only that Mel indicated they were leaving today. Said he had to get insurance and visas.
Roland
Well after waiting for around 2 hrs on the highway to meet them at what I figured would be his arrival it is now dark and I am thinking the worst, my phone rings and it is them calling to say they pulled into an rv park in Santa Ana which is about 4 hrs from here!!!
At least they are ok!
He does say his alternator is not working and so they do not have to use headlights they stopped for the night.
Should arrive around 1pm. Then we have to figure out what is wrong and if this alternator can be made to charge batteries etc.
Keep posted.
Johnh
Yes for Mexican liability insurance and passport.
No car/vehicle permit needed the in "hassle free zone" in Sonora to just past Guaymas/San Carlos where John is. Buy Mexican liability insurance online and you don't have to stop. Sonora Only Program - Mexcan Vehicle Permits - Mexbound Mexico Insurance (https://www.mexbound.com/sonora-only/) No immigration papers either.
John, another member called me and if you have time, you may have to help the polliwog's getting to San Carlos.
Map below
Pierce
Well they finally arrived at 12, 30pm safe and sound .
We are going out for supper to talk.
John
Hope today to start the testing to see what is going on .
Mel said that he had no snake eyes the whole drive but that maybe he had the boost on and solar kept battery up as sun all day .
Will find out what model of alternator he has. His genset is not working either so another issue to address. Looks like we are going to be busy.
Johnh
Ya, the root cause of his snake eyes could certainly be very low voltage to the Allison ECU.
Amazing how finicky electronics designed for 12+ VDC can get at 10 VDC.
If John verified the ECU and shift pad are good, voltage is absolutely the next step.
No "I told you so" but with the twin digital voltmeters on the dash, you never have to ask about voltages or batteries or if the alternator is working. I think they cost $8/ea. I never turn them off so they've been on for years. Great going down the road, at a campsite or in storage.
Same goes for ULSD fuel. It needs an additive to make up for lack of lubricity in the ultra low sulfur content diesel unless you are running biodiesel. This can cause stuck injectors or pump failure.
What's the oil filter jingle? Pay me a little now or a lot later. How much is time, inconvenience, $$$ worth?
Pierce
So we have he genset now working and making power,one down, and checked battery cables connections some not tight but are now. Trying to figure out the wiring for them and find cables from charger when hooked to shore power. Have a charger on engine batteries to bring them up to test the loss if any from them. Solar working well on house batteries so if we are not able to fix the non charge issue from alternator we will switch the solar over to chassis batteries for drive home. Have not looked at alternator yet. I told him maybe when we get back to home we will put the coach on my pad and totally remove the isolator panel etc and rebuild everything with new as it all is just a mess of rust and original equipment.
Bit by bit it will get done.
Johnh
I got a couple of these to plug into the dual 12v sockets in the dash. On our 2004 one socket is on the chassis battery and the other is on the house battery. They have a voltage display and have one standard USB and one USB-C.
Amazon.com: INIU Car Charger, 66W Total Dual Port [USB C+USB A] 6A QC 3.0 PD... (http://www.amazon.com/gp/product/B0946VSWKH/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1)
Ok good news, his alternator was not toast so after talking to Peter Fleming we did the moving of cables so alternator feed and chassis batteries are direct connected and removed the excite wiring and relay that the shop put in that installed the Delco alternator 2 yrs ago.
It now charges chassis batteries 14.4 and solar is looking after house ones. Once back at my place we are taking all the wiring apart and replacing Breakers solenoid and isolator so it works as designed with the Delco alternator.
Thx to all for help now Mel feels a lot better.
Johnh
Have been home 3 days and working on various issues including Mel's charging issue.
Bought the Delco Remy isolator and installed it along with sense wire etc. Both battery banks are now being charged so that one is done. Again a big shout out to the Forum and Peter Fleming for the help sorting it out.
Now he has another issue that started tge last day of driving here from Mexico and I will start a new topic to keep it seperate.
Thanks
Johnh
I was having similar problems. search MD3060 transmission I don't know how to put it in this post. Look at reply 19 and 20. It has some pictures and where I found my problem with voltage to ECU.
I hope this helps
Ron
Ron,
Here you go
MD3060R Transmission (https://www.foreforums.com/index.php?topic=41910.msg418825#msg418825)
Pamela