We are about an hour north of St Paul, MN. At about 55 MPH, the coach lurched, the Allison panel showed what looked like two arrows, and we lost propulsion. I coasted over and shut off the coach. Now the key won't start the engine, and the Allison panel will not light up, and does not respond to any button-pushing.
I checked the trans fuse in the fuse panel, checked for power at the fuse, and still nothing. Good power from the batteries. Is the trans and engine not starting related?
Any quick ideas before we call for a tow?
oldMattB
Found ATEC fuse blown. Still no start, Allison panel shows two lines with slashes, will not show diagnostic codes.
Matt,
Pull the white cover off the breaker panell in the basement and see if you have tripped the 90 amp breaker that feeds the ignition.
Pamela & Mike
Matt, I have had excellent technical service experiences with the Allison local distributors by phone. I found the following on the Allison site.
Interstate PowerSystems, Inc.
Allison Distributor
2501 American Boulevard, East, (Bloomington)
Minneapolis, MN 55425
Phone: 952-854-5511
Fax: 952-854-2999
Maney International, Inc.
Allison Dealer
375 S. 33rd Avenue
St. Cloud, MN 56301
Phone: 320-251-9511
Fax: 320-251-9523
Matt,
Sent you a PM-- call if that is easier.
Do any other things that normally work only with the ignition on not work (i.e. dash HVAC fan)? If so, look at the ignition solenoid which is under the left side of the dash just behind and toward the right of the fuses for transmission, etc. Check for 12 VDC to one of the large lugs (battery side) and then only with ignition on, to the other large lug as well. This will confirm not only power from chassis battery to dash, but also that you have power on the" ignition on" side of the solenoid. Note: I have seen these solenoids fail not just in the "won't work" mode, but also in the high resistance mode. In high resistance mode, it will be hot to the touch and there will be a significant voltage drop from chassis battery side to ignition on side.
At least on our 1993 U240, the wiring schematic for the transmission is A4593. Sorry, I am at home and don't have a copy in front of me.
It likely goes straight down to the Allison ECM on the front firewall in front of driver's pedal area, but that is just speculation. You will also have the plug going from ECM to the shift pad.
If you find that you have an ECM or shift pad issue, before spending big bucks on a new one:
Allison ECU and shift pad repair: Transmission Instruments (http://www.transmissioninstruments.com) 866 439 9779 John Kopalek.
Brett
the three big breakers are all passing 12-volts +
oldMattB
Matt, call James Trianna or Mark Harmon at FOT - 800-955-6226. Choose ext. 5 for James and I think Mark is ext. 256.
If you haven't tried Brett's suggestion about the items that go through the ignition switch you should do so. I just had to change out my ignition solenoid as have several others with coaches of this vintage.
Check for 12 volts at ignition solenoid under dash (left side constant 12v from battery) and check it to see if working. If no power there, check the other end of the cable at terminal #1 back at the battery isolator. If ignition solenoid is bad, replace with Cole Hersee solenoid part number 24143. This is continuous duty. Intermittent duty replacement will get you to the next town. See photo below.
This works on mine but not saying that yours is the same.
dash solenoid replaced recently and flowing 12V+ when key turned
atec fuse blown and replaced
no oil slick under coach
checked 3 trans fuses
checked engine starting breaker
removed and replaced trans panel connector and 2 computer connectors
parking brake on
waiting on return calls from FT and Allison
oldMattB
Matt, I just reread you first post. The reason the engine is not starting is probably because the transmission is still in gear. Until you can get the tranny panel to respond to a gear change to Neutral, the ignition lockout will probably prevent the engine from starting.
Matt,
Here is the ATEC interface schematic for my rig. Hope it helps.
It is possible that Pierce's schematic applies to your coach, but the U300 has a totally different transmission (4 speed), not the 6 speed electronic MD3060 6 speed you have.
OldMattb, On my 95 this happened in PA. Turned out that the wire from the ignition source at the remote start panel to the isolator had melted insulation and shorted to the block. When pulled loose off block all was well. Wire replaced. Don't know if yours has same wire.
Good Luck
Gary B
Ya, the first split in the "diagnostic tree" is whether that fuse keeps blowing. If so, that needs to be solved first.
Brett
Took ECU to Interstate in Bloomingdale. They tested it and it was dead. We are headed back to Onamia and are hoping Grandzilla is still there! I will check remote start wiring. Thanks all for help and we will update later.
OldMattB
Hey Matt, please let us know when you get her fixed and what caused the problem.
John Anderson at Interstate Power Systems is our hero. (thanks Kent) Interstate - Home (http://www.istate.com) He tested the old ECU and verified that it was dead. He opined that a failure in the unit circuitry caused the fuse in the dash panel to fail. He programmed a new unit for us and sent us home. I installed it and we were back on the road. Not a cheap fix, but we avoided a tow, diagnostics, and installation. I am pleased overall. Mr Kopalec, the ECU repair guy is on vacation until 9/28, and we were not wanting to camp 1.5 feet from the traffic for that long.
Mr. Anderson warned that the toothed ring that drives the speed sensor is prone to failure (I think I am getting this right). It is underneath the sensor and is called a "tone ring." The 1993 build year used a pin that is soft and wears easily. We can check the condition by removing the sensor and attempting to move the toothed ring. It should not wiggle. If it is worn, it will cause erratic shifting.
ALSO, he suggested Weller Truck Parts for replacement transmissions if one is too far gone WELLER TRUCK PARTS | WELLER REMAN (http://www.wellertruck.com)
Thanks again for all of your help.
oldMattB
Bummer that you broke down. It's great news that you are back on the road AND MOVING under your own power.
Thank's for sharing your experience.
Have been following oldmatt's issue, unless I missed something, I wonder what happened first. Can not picture the ECM just rolling over dead for no reason, I am guessing some event happened to cause it to croak. Goes back to the old chicken or the egg story. Just wondering thoughts.
Am very delighted oldmatt is up and running, Know that was not a low buck fix.
I just wonder if the root cause has been found/fixed. Anything from loose wire-bare wire shorting to ground ?
Glad your up and running again Matt!
I hope the root problem is solved. Mr Anderson opined that the ECU failure was the cause of the blown fuse, though he cautioned to look for other symptoms and to check for error codes after the initial clearing during installation. The failure was on a cool day, smooth road, etc. and etc. No temperature, humidity or shock extremes that I would expect to make a problem into a failure. I hope my story ends with the new ECU.
Thanks all!
oldMattB
Friends,
This is our 1st post on your great Forum - hope this is not off-topic.
It appears oldmattb's travel interruption was caused by a failure of the ECU.
We are prospective Foretravel owners and wondered if you could inform us as to those years in which Foretravel offered mechanical, non-ECU Cummins powered coaches.
Sincerely,
Robert - Cape Coral, Florida
I may not have read closely enough, but I thought it was caused by the transmission ECU. Mechanical engines and transmissions petered out around 94. The u280 with a Cummins 8.3 and Allison MT 647 4 speed is a fine coach. The mechanical 8.3 continued up to 98, but it was paired with the electronic 6 speed. If you want a trans retarder or a Jake you will get electronics in a Foretravel.
Very rare failures, but it does happen... No more often than having to do a complete engine or trans rebuild.
I'm one who appreciates the basics. I always thought I preferred mechanical powertrains. That is why I have owned two 1993 coaches. However, as it turns out my current 1993, U300 has both an electronically controlled engine and transmission. I now recognize there are many benefits to the electronics and they actually improve the analysis any problems.
If you truly want a mechanical power train, one of our forum members, jor, has a 1993 U225 for sale that has been extensively upgraded and is priced very right. You can look him up in the members section and send him a personal message if you are interested.
We would love to have you join the Foretravel family. There is no better value in class A motorhomes than a well cared for used Foretravel.
I have a 98 u295 with 8.3 mechanical engine that I will be selling shortly. I live close to Tampa. my phone is 813 215 3463 thanks Ron
Kent is quite correct that any problem with the engine or transmission can be quickly diagnosed if it has a computer controlled engine and transmission. Not only does it make driving almost idiot proof but cuts the emissions considerably.
An all mechanical engine/transmission/air suspension RV does give a bit more piece of mind, especially for those of us that might be off the beaten path and a long way from help. But, as Dave said, these failures are few and far between. Reading about them does effect the confidence a little though. Another reason to know exactly what ECU you have. Actually, if the part number is known ahead of time, a very reasonably priced spare can usually be found on ebay, etc. But then, you could fill the cargo bins with spares.
The problem here is most of the computer controls were designed for fleet work where a bus or trucking company could send out a repair truck and would also have the necessary parts in stock to quickly get the rig back on the road again. Nice to have a support team like that.
I would like to see the next generation of RVs have computers with a separate "limp home" mode so while the engine or transmission might no longer be operating at it's best, it could be driven a reasonable distance to a repair facility and not leave a family stuck by the side of the road. Many current cars have this already. Perhaps I am a bit behind the times and some have this now.
I believe most computer controls have emergency systems as part of the programming. If a component of the system is not operating properly, the computer stores a code describing the failure, and if possible we drive on. If proper operation of the component is critical, the computer protects the transmission from having us stupidly destroy it.
Anyone else know more about this?
In my case, the ECU itself failed catastrophically. It smells like smoke and has parts rattling around inside. A new one was $2800 with tax, which might discourage some from carrying spares.
oldMattB
We experienced the "emergency systems as part of the programming" for the ECU on the transmission of our previous coach.
While driving in blizzard conditions, the Allison MD3060 transmission on our SOB coach went into "limp" mode. We could operate in 1st, 2nd, and reverse gear only. We were able to get to a safe place to park. Coach-Net helped us interpret stored codes as "loss of speed sensor." After weather conditions improved overnight, I was able to go under the coach and reattach a connector that had been pulled apart from the weight of accumulated ice.
We bought the FT to replace the SOB so that we can "hunker down" and wait for a blizzard to pass. In the SOB coach, we chose to flee to warmer conditions because the SOB coach could not protect us from the cold.