| Author |
 Topic  |
|
|
earl1412
Senior Member
101 Posts |
 Posted - 03/03/2016 : 1:49:20 PM
|
Does anyone think the school bus community would be cohesive enough to get Congress to allow the reprogramming of DEF engines to stop the derating of engine power during a malfunction? I know the fire departments across the country can pay to alter the programming, and for the reason of child safety, I think these vehicles should be able to be reprogrammed.
I don't want to stop the use of DEF or alter the emissions in any way, but I've had alot of issues with the Cummins sensors getting out of specifications during extremely cold weather, and the buses would derate to compensate for a non existent problem.
I really am having a hard time accepting that the fates of up to 75 people onboard these vehicles are left in the hands of some engineer making a sensor that is designed to fail so the manufacturer can sell you more parts.
What do you think?
earl
|
|
|
krmvcs
Advanced Member
362 Posts |
Posted - 03/03/2016 : 2:51:57 PM
|
heres one of my posts from a previous discussion....
not sure if i mentioned this before but here goes....
ive had a few strange things happen with these systems generally involving the float level sensor in the tank. sometimes they get stuck at the bottom, and sometimes somewhere in the middle. heres the kicker, the ecu (cummins anyway) trusts the level sensor over the sensors on the dpf and scr. for example: full tank, sensor stuck at bottom, check engine light on and derate, limp mode after shutting off engine. empty tank, sensor stuck in the middle, no worries. i had one run with an empty tank awhile until it dawned on me that i hadnt filled it for a couple months. gauge read full and the tank was bone dry. ive asked a bunch of different people about this whenever i went to training events and nobody has any explanation. specifically why does the ecu trusts the float sensor over all other sensors reading the output emission conditions? thoughts?
|
-Ken- |
 |
|
|
Bassman
Top Member
USA
558 Posts |
Posted - 03/04/2016 : 03:38:12 AM
|
| You guys probably know this but there is a reprogramming to make the thing less sensitive to goofy nox sensor readings on the cummins and that has helped us a lot. We purchased the upgraded software and the necessary interface to do our own reflashing, but you better put a tech on it that knows what they are doing. Can't even imagine what could happen if we would goof that up! |
|
|
|
bwest
Administrator
United States
3820 Posts |
Posted - 03/04/2016 : 05:32:21 AM
|
quote:
Originally posted by earl1412
I really am having a hard time accepting that the fates of up to 75 people onboard these vehicles are left in the hands of some engineer making a sensor that is designed to fail so the manufacturer can sell you more parts.
Correction, the engineer (for which there is no love lost from me) really has no choice in these matters. We are the ones who have a choice and that's when we elect our government officials. Do I want dirty air and water? NO and NO. However, I want safe kids and sometimes these conflict. Just sayin' |
Bryan |
|
|
|
Thomasbus24
Administrator
USA
4547 Posts |
Posted - 03/04/2016 : 09:05:33 AM
|
I'd support it, but I have no idea where to begin.
Just a few weeks ago a neighboring school had a 3 year old bus at a basketball game that wouldn't go over 5 MPH when it was time to leave. It was screaming that it was out of DEF when the driver started it up to leave. It wasn't.
Towed in, worked on, Cummins denied the warranty saying that the driver ran it out of DEF and walked somewhere, bought some, and filled the tank. Yeah, ok, sure pal. Watch the video of the bus driving down there with no alarms going off and tell me that.
What if it had decided it was out of DEF on the freeway? That'd be nice. |
|
|
|
bluebirdvision
Top Member
USA
1081 Posts |
|
|
exmod110
Senior Member
151 Posts |
Posted - 03/04/2016 : 11:07:09 AM
|
| how does a derate endanger children? the bus is running, producing heat and has the ability to move. Sounds more like an inconvenience to me. We run in in temps down to -39c with a winter average in the -20's c with minimal issues from the Cummins engines and emissions. We do not have LOTS of them, but the ones we have are gold compared to any recent emissions IH engine we have. |
Edited by - exmod110 on 03/04/2016 11:18:45 AM |
|
|
|
aaronwilmoth80911
Top Member
538 Posts |
Posted - 03/04/2016 : 1:46:57 PM
|
We have buses that run the interstate at 75 MPH, and when one derates, it becomes a very big hazard. Even if the driver pulls off to the side, sitting on the side of the interstate is a hazard in itself.
If this can be done, I think it would be a good idea. I will continue to follow this post to keep abreast of the situation. |
|
|
|
torque
Advanced Member
Canada
358 Posts |
Posted - 03/04/2016 : 1:48:09 PM
|
At 8 kph (5 mph), that bus gets pretty long if a train is coming and you are trying to cross the tracks :)
It isn't like the old derating, they slow it to a crawl now. Not even safe for the technician to drive on the side of the road to get it home so it turns into a tow call. Before they had some sense when manufacturers were not allowed to shut down a school bus or a passenger vehicle for an engine or emission fault, but at that low a speed you may as well shut it down. You can thank the tree huggers for that LOL. Sacrifice a bus load of children, but hey, we saved a tree :)
Anyone else notice they changed it from GLOBAL WARMING to CLIMATE CHANGE? I notice that after the last couple of years when we had record cold winters :) This year not as cold but record snowfall. Yes lets clean up our act, anyone else remember when New York was under a glacier? Me neither, so I guess the warming of the earth started long ago. Have a great weekend. |
|
|
|
ICBUS07-30
Senior Member
USA
59 Posts |
Posted - 03/04/2016 : 4:12:22 PM
|
| Its said when you have to pay 400$ to tow a two year old bus two hours away to a dealer for emissions crap and comes back only to happen again.But I guess that's what happens when you put to much technology on things they should not be on. Don't get me started on DEF complete waste of money. |
Formally ICBUS0730
|
Edited by - ICBUS07-30 on 03/06/2016 09:13:42 AM |
|
|
|
g0ttadrift
Advanced Member
USA
258 Posts |
Posted - 03/04/2016 : 5:00:34 PM
|
| I agree completely with you guys. We have about 10 buses with DEF and luckily no problems. But we have had some driver's run them empty and you do have to tow them back if they derate. 5 mph is more of a hazard than just shutting it down completely. I think Congress should change this law and I would be interested to see where this post goes! :) |
|
|
|
earl1412
Senior Member
101 Posts |
Posted - 03/05/2016 : 05:48:11 AM
|
quote:
Originally posted by bluebirdvision
Back when I worked in the warranty dept for the BB dealer here. I believe there is a revision to the Cummins software. We did it free for customers.
Would you be able to PM me? I have a personality conflict with some service writers, and would love to know how to get this revision done without hassle, (ie Cummins or BB TSB or similar).
Thanks
earl |
|
|
|
bluebirdvision
Top Member
USA
1081 Posts |
Posted - 03/06/2016 : 2:45:59 PM
|
| I don't work in that capacity for the dealership anymore, and I have washed my hands of it. HA call your dealer. I just drive 'em now. |
Facebook Page: Blue Bird Corporation Fans
https://www.facebook.com/home.php?sk=group_212311114614&ap=1
|
Edited by - bluebirdvision on 03/06/2016 2:46:32 PM |
|
|
| |
Topic |
|
Reprogramming to stop derating of DEF engines
