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Roy Belding
Roy Belding, RV Mechanic
Category: RV
Satisfied Customers: 4490
Experience:  10 years expierence on all makes and models
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My 2002 Frieghtliner RV is showing code of MID: 128, SID:

Customer Question

My 2002 Frieghtliner RV is showing code of MID: 128, SID: 254, FMI: 8. (currently have 211 of these stored)Issue has become more prevalent over past few months. I can usually get check engine light (and limp home mode) to go off by using exhaust break. I've checked all connections at the battery, grounds, etc. I've contacted local freight liner and have been told my unit does not have a ECU power relay.What else could be causing this?HD code READER says Engine #1, Controller #1, Abnormal Frequency, Pulse Width, or Period.Last 6 of VIN is L01055Previous answer from from Roy was:
good afternoon my name is ***** ***** I will assistThat code usually means there is a problem with the power connections to your ECM which could be anything from loose battery connections to bad ECM power relay. That code translates to 626 which is an unexpected reset DTC. I have found alot problems at the small power and ground connecters at the battery which go up to the ECM power relay.
check all connections including the batteryRoy
Submitted: 5 months ago.
Category: RV
Expert:  peterpete190 replied 5 months ago.
My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.My info is somewhat limited on your model here but I had seen no one else has responded and would like to see if I can help here.If at any time you feel that I cannot help with this please let me know. If you havent checked for any damaged or shorted wiring or even corroded connections at the ECM and leading from the ECM this should be done.If there are any issues with damaged or corroded wiring or connections this will need to be repaired to correct this issue here.If this is or was checked and found to be o.k. let me know so we can continue from here. If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.Thanks Pete
Customer: replied 5 months ago.
Still looking for assistance, thank you for the response. I have checked all connections with the ECM, as well as every other power relay I could find. Any other ideas on troubleshooting techniques I can try? I've tried different code readers as well as voltage meters to see if things were effecting system voltage.
Expert:  peterpete190 replied 5 months ago.
Unfortunately my info is limited on this model here.I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.Thanks Pete
Expert:  Roy Belding replied 5 months ago.
good morning again I responded to your post and you never responded back to me. I see Pete assisted. do you want to continue with me or do you want someone new??? if you want to continue I will need answers to my questions to help you Roy.
Customer: replied 5 months ago.
Roy, would like to continue with you. I tried to respond when I returned but the listing was closed and I had no way to contact you directly (I tried).What questions can I answer for you that might assist me? Thanks.
Expert:  Roy Belding replied 5 months ago.
ok, lets go back to my original answer. what is the voltage of the batteries???did you clean all connections at the battery??? low voltage codes always revolve around the battery area. lets make sure there is no issue there yet Roy
Customer: replied 5 months ago.
Voltage good. 12.5 resting, climbs to 14.1-14.2 during normal running. Tested both batteries with CCA tester, no issues. Disconnected and reconnected all terminals. Ordered and have been running SCANGAUGE D so I could get voltage from the ECU while driving and not just the 12v outlet. It's steady, and matches what is on my other Voltmeter readout via 12v wire.Is it possible it's not Low Voltage? Thanks for continued dialog. I can't wait to get this issue resolved.
Expert:  Roy Belding replied 5 months ago.
it is but must verify the batteries are supplying ample voltage. sorry, was teaching all day. let me do some research Roy
Expert:  Roy Belding replied 5 months ago.
ok, it is power interrupted to the ecm, as we know, this could come from low voltage, most common, dirty battery cables, loose connections at the battery.if all that is good, then power is being interrupted either from a harness issue on supply lines to the ecm or the ecm itself failing internally.
Customer: replied 5 months ago.
This was my last email with a parts guy that used to work at Orlando Freight liner when this started happening only when I was going downhill. Is something like this possible and I just haven't looked under the dash enough?"I think your vehicle is experiencing an overspeed condition which is normal based on your engine ECM parameters (travelling downhill can cause this) and the fact that the code is inactive. Attached is what I found based on the codes on the screen (MID: 128; SID: 254; FMI: 8) however, I am unable to locate the switch mentioned in the attachment. If there is such a switch it would be located on the dash of your vehicle. I spoke to Service and the opinions were inconclusive as to the cause of your inactive code. Perhaps a call to Cummins Northwest to get a second opinion would be in order. I’m not sure of your location or else I would be able to provide a phone number."
Expert:  Roy Belding replied 5 months ago.
did they pull the ddec reports to confirm the overspeed??? Roy
Customer: replied 5 months ago.
Negative. This was me pulling the code while I was working a job up in the Northwest when this problem started last summer.So just a phone consult with a Freightliner parts guy who has been really helpful on getting my parts/pieces and such for this and my other government rigs.It didn't seem right to me either, as now sometimes the code happens after just a fresh start.
Customer: replied 5 months ago.
You mentioned in the first email about a power relay for the ECM. Freightliner says my unit doesn't have one. Is it part of the ECM on my model, or called something else?
Expert:  Roy Belding replied 5 months ago.
it is part of the ecm internally. it is interesting they made that statement about over revving without pulling report. that would confirm it Roy
Customer: replied 5 months ago.
Yup. well, he is a parts guy, not a mechanic. What would you recommend next? Should I take it in to get the additional data from computer read? Any other crazy places I could check before I am in for a few thousand dollars? :(
Expert:  Roy Belding replied 5 months ago.
they made the claim that you over speed the motor. put the ball back in there park and prove it. Roy

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