I have a 2000 Fleetwood Discovery with the Cummins 275ISB and have used VMSpc for years (Currently v3.0 Build 1.) I'm getting the following diagnostic code: ENG SID 65 7 Heated Oxygen Sensor Not Responding 10/28/15 9:56 The problem is my engine does not have a Heated Oxygen Sensor. Is there any way I can find out what this failure code is really referring to? I've noticed in the past that VMSpc codes don't always correspond to Cummins diagnostic codes. Thanks for any help. Pat Curry

Submitted by Art on Sat, 2015-10-31 15:25


Hello Pat Our codes corrolate to the standards which the engine builders are required to use by the EPA and others. That standard is the J1939, J1708 and J1587 for the large diesels. The code reported is the code the ECU is designed to produce under...some seemingly odd...situation. Very odd. I'll have a look to see if there's some other way to explain this but for a MIA sensor. cheers Art //

Submitted by pjcurry on Mon, 2015-11-02 08:22


Hi Art -- Thanks for the reply. As for the codes - we recently had an injector pump go bad. I got an orange check engine light and the engine derated to zero power. VMSpc did show a problem and a code. However, when the Cummins tech hooked up his factory diagnostic device (not sure what its called) it showed a completely different code. We went through the "guide cards" for his device and his code showed up but the VMSpc code did not appear anywhere in the Cummins literature. I get a bunch of weird codes on my VMSpc (notices from cylinder (EX: Injector Cylinder #18)and I've never been able to find out what they mean. Here's some examples: ENG SID 48 0 Injector Cylinder #18 High Reading 10/28/15 9:56 ENG SID 66 8 Ignition Control Mode Signal Frequency Error 10/28/15 9:56 ENG SID 65 7 Heated Oxygen Sensor Not Responding 10/28/15 9:56 ENG SID 48 7 Injector Cylinder #18 Not Responding 10/28/15 9:56 These are only a few examples of many. Sometimes they show up in the "Recent Diagnostic Events" pane and sometimes only in the "History" pane. I don't get a check engine light. None of them show up in the Cummins literature and I haven't been able to find anything on line. I'd sure like to find a way to determine what these codes mean, if anything. Thanks again for the reply. Pat

Submitted by Art on Mon, 2015-11-02 14:42


...very predictable... Hello Pat. The literature reflects "living in a vacuum" where theory abounds and reality is suspended. It gets really tedious when the software written doesn't do--or produce--the things its supposed to without creating new problems. This is the case with Cummins engines. Mechanically great; however there are some issues which are never going to be "in the manual." I rarely/ never hear of this in conversations of IHC, Detroit', Cat or Mercedes or anyone else. Its common enough to see these codes appear on a ISL, sometimes ISB and ISC. The stray codes are result of crashes on the data bus when messages are batched-up then, once delivered, divided apart. If the simple math is wrong or a single message gets corrupted, the results are a potpourri of derivative messages. Usually, a code relating to a real problem is on the list. It will be accompanied by a group of "like minded" errors. In your case, the pump, which didn't report correctly or suffered so many corruptions that it couldn't be interpreted on-the-fly. We don't have a filter to limit what messages the engine produces. We don't have a table to choose from--the messages you saw were the ones on the bus, from the ECU, at the moment you noted them. However, I've suspected the Cummins-centric scanner is designed to only show a group of items and not "Illegal" ones. One of the ways this is side-stepped by Cummins it seems is by using "Cummins Codes." These are their own trademarked codes. Its a different set than what the engine actually produces--in that each is more group or area-of-defect specific. So, on the one hand, a generic scanner (listening on the J1708 diags port) will show the codes the ECU is actually producing. The Cummins "Fault Code Advisor" unit however transposes these to their set AND will only display their, special, set. It will not display a standard SAE code set. For their techs, it doesn't exist. It would appear to be a business model...but, I'd be guessing. We display the codes as the databus is supposed to comply to. The standard doesn't force an engine builder to use a certain maths or CPU, only that the SAE codes conform to the J1587, J1708 or J1939. As such, we will display what DM1 codes the ECU throws. After all, we have 90-some engines by many makers to contend with--so we must stick to the same process for all. We can't really fudge the system to compensate for their stylized methods. I hope this helps cheers Art //