ECM Question

Joe Camper · June 05, 2011, 03:05:10 PM

2000 60 series XLII dash says check engine next stop . It can be reset on the dash reader and the bus will go. The bus runs even if we dont clear it.

The code is ECM backup battery and it will not shut the bus down even if continued to be reset, according to Prevost.

They also say the fix is a new ECM so I assume somwhere built into the module there is some kind of d/c power source for the memory? Im guessing anybody confirm or corrrect this.

Anyho how much is a new ECM now anybody know?

JohnEd · June 05, 2011, 03:20:52 PM

Is the battery the "keep alive" voltage for volatile memory? You can't solder anything on to a printed circuit board that can't be replaced. Loosing that would mean that you needed to check the codes before shutting down?

What is that "CRUEL HUMOR" on the part of DD? Doesn't a ECM cost a couple grand? Replace every three years like your watch? This reeks. Who are you really?

John, always aghast at the cost of stuff.

luvrbus · June 05, 2011, 03:28:36 PM

Ecm's on the latter model series 60 engines have a battery back up built into the unit non replaceable you will need a new ECM and have the clock set 3500 exchange from DD last I got from WW Williams for a 14L @ 515 hp that one should be a DDEC IV 12.7 maybe cheaper

good luck

Joe Camper · June 05, 2011, 07:42:33 PM

What will be the result of doing nothing but reseting it every time?

There will be no memory of past codes? Is that all?

JohnEd Im not sure could you translate.

JohnEd · June 05, 2011, 09:57:25 PM

I am out of my element. i got some tronics smarts but even those are dated.

There are two kinds of memory. One endures and will stay set(remembering) even after power is removed from the unit. That would be like the disc memory in your computer. The other type is volatile....it erases every time it loses power. Some appliances such as clock radios and especially auto radios will lose their memory if the power or main battery is disconnected. Clock radios used to have a battery in them and its only function was to "keep" the memory protected if you lost power to the radio during the night....alarm times and time and date etc. Clear?

Your DD Dealer said you would be OK to drive the bus with that condition. They didn't say for only 20 miles or 2 days or under 55 MPH. For 3.500 smackers I would put up with the code. Like I said, if the engine throws a code while it is running, you will be able to see the code before you shut down. If the code shuts you down then you will see the code till you shut down power to the ECM. Remember, my first statement on my qualifications was that I had none.

You can verify everything I have said on the board. i will start it off for you...watch.

Good luck and I hope this helped a little.

John

JohnEd · June 05, 2011, 10:05:40 PM

Can anybody post a pic of the ECM module...front and back? A detailed IPB or illustrated parts breakdown would be even better. But the pic or a actual ECM would do the trick. Not a guarantee by any stretch but I made a handsome living for years doing stuff that was said to be impossible. There must be a bunch of these laying around with dead bats as bats are know to not usually last forever and the 60 has been kicking for quite some time.

John

Zeroclearance · June 05, 2011, 11:38:25 PM

Joe, three summers ago, I had the very same thing happen. The DD tech just reflashed the ECU. It is a known issue. The new program disregards the internal battery. I also had a warranty update >> new MAP sensor and wiring harness.

Joe Camper · June 06, 2011, 04:10:31 AM

Thank you everyone.

Someone get JohnEd a couple photos of the ECM I believe he may just show us all how to fix it.

If I have to pull ours I will do it then for, but money will already probably be being spent by that time.

Threw the same question on Deisel Chat.

Trust but verify, LOL, a great quote I like to borrow. Bet many know who coined that term

luvrbus · June 06, 2011, 05:28:45 AM

That is good to know Fred but where does the clock get it's back from if the battery is bypassed it is a computer and has to have a battery to operate ?

JohnEd · June 06, 2011, 06:02:23 AM

Clifford,

Remember when Ace had the problem with his ECU and it turned out to be with the two 12 volt power lines from the bat tray? Interrupting those power lines stopped the ECU and the engine. A back-up battery doesn't actually power the ECU, that power comes from the engine bats. The back-up just powers the memory to preserve error code data between power down periods.

If a DD tech will flash the ROM to eliminate the error code then I would accept that as the fix. $3,500 is a powerful incentive for a "work around". I wouldn't waste time on the back-up bat. Considering those 12 volt lines to the ECU aren't apparently switched and the engine bats are connected at all times. You would probably only use the back-up when you interrupted the engine start bat power and how often does that happen? In the military we called this a "procedural fix" for a hardware failure and that sometimes is all it took to get back up and operating.

John

luvrbus · June 06, 2011, 06:10:36 AM

Ace has a older DDEC John we are talking a IV here,I just would like to know where the clock gets it power if the battery is bypassed.Cummins had a lot of trouble with this when people replaced the factory starter with a rebuild the ECM would die costing big bucks starters and the ECM together lol

good luck

Joe Camper · June 06, 2011, 08:00:49 AM

Thanks a bunch again.

Here is what i started at another forum and hoping for some additional answers to get all our options.

http://www.dieselenginetrader.com/diesel_talk/messageview.cfm?catid=9&threadid=4866

Zeroclearance · June 06, 2011, 08:14:54 AM

Detroit has a bulletin to reflash the ECU. The link that Joe provided has "GoneFishin" tell us>>
DDC recommmends a reprogram of the ecm. $500.00 . This is to remove the code from showing up.

He is a respected DDC tech. He also mentions that he hasn't had much luck with the reflash.

My reflash has worked well, however if I had checked into the battery info, I would get a battery holder and the 3V Sony battery!

Hard Headed Ken · June 06, 2011, 08:52:55 AM

Here's something I've heard from more than one truck driver. When an older ECM is flashed with the the new software unfortunately that includes the newest possible emissions changes, different timing tables, different smoke control table, different fuel map, etc. That all claim lowered performance and fuel mileage after the reprogram. I have have no way to confirm this, I hope someone on the board may know if it's true or not,

Ken

Zeroclearance · June 06, 2011, 09:07:02 AM

Ken, the file that was flashed resulted in 1/10 of a gallon increase in fuel milleage. That might be from the addition of the map sensor and new wiring harness?? I have been really happy with my DDEC 4..

I re-program Bosch ECU's and I have many times thought that I should take a peak into the DDEC code. The factory codes are typically conservative. Slap the bus on the dyno and Run-it!!