Hi All, Kobelco 140, engine Mitsubishi D04FR-KDP2TAAC Customer went to start her up in the morning and machine showed error 20411 "DBV valve opening". From what I could find out this is a commonrail overpressure protection vavle. Machine only idles in this condition, doesn't allow to rise RPM. I came to site, checked and cleaned jacks for pressure sensor, and low pressure regulation valve (MPROP I belive it is called) and error went away. Machine started and worked fine for a few hours. 3-4 stops and starts later, it came up with same error. Customer shut her down and started up again few times, and error went away again. My bet is that pressure regulating valve is somehow sticking. Did anybody have an issue like this before, or similar? From what I can see, ECU determines opening of DBV valve based on signals to low pressure regulator, and high pressure sensor, if these don't match, it determines that DBV valve has opened. So, problem may be high pressure sensor, low pressure regulator valve, or DBV vale. I'm on the right track here?
If I remember correctly, there is an overflow valve at the end of the rail.. it’s a banjo bolt.. They have a tendency to break the spring inside of the b bolt.. Give that a try..
Your DBV valve plug is disconnecting or missing thats why the error code is showing. You have to fit the plug properly. The plug not fitted tightly so the error coming. Fit the plug with a clip. When the engine start the engine vibrating and mising the plug. I have given the DBV valve picture it will help you
I will inspect the spring thanks!!!! Well can somebody clarify for me what DBV exactly is? I taught DBV is screwed one end of commonrail and in case of overpressure it opens and drains the fuel back. It has no wires attached to it, it is controlled just by the force of the spring. What Sourov1 sent me I belive is fuel pressure regulator valve on low pressure side (MPROP). Am I correct? I like the touch with zip ties
DBV is German language!!! In German it is abbreviated by D ruck- B egrenzungs- V entil = Pressure limiting Valve. Error code 2041-1 is DBV valve opening. You can see attached file for more details. Good luck.
You are right. Can you give me the service and parts manual please. [email protected] thank you
Sorry I don't have manuals for this excavator. i found information from training manuals for different model and from engine manual. All I found on the net.
Mprop regulation valve replaced. All working well. Thanks all for the support!
Nope!!! Worked for half a day, then same error came back. Off to check it out tommorrow. Can it be dirty fuel that is getting the valve stuck?
I'm having similar issues on my Sumitomos. Not sure if its dirty fuel stuffing the suction control valve?
I didn't have a look at the replacement valve yet. Because I had another call from this customer saying that operator fiddled with some wires and error went away. Original valve, that caused the fault, didn't make any movement when voltage applied to it, and no "click" was heard from it, but it had same coil resistance as new valve. Which means it was mechanically jammed. i don't know what kind of dirt gets thorough pre filter, and 2 fuel filters and jams valves. unless fuel filters are disintegrating and sending particles downstream. Mprop valve can not be taken apart so I can't inspect it inside. I asked the customer about when it was last serviced, got back 5 seconds of silence, which means.....sometimes in the past....... so in my case, it can be anything causing this to happen again.
Machine was on hold so to speak for few months, back in action now. Same fault coming up. Went over there today and changed DBV valve as well, no luck. Only thing left to change is the fuel pressure sensor. Or the pump it self can not jack up the pressure expected, so the ECU thinks that DBV valve is open, It must be that ECU expects certain pressure calculated from engine RPM, load, and MRROP valve actuation, if pressure information sent back from the pressure sensor is not what it expects, it assumes that DBV valve is open. I can not conclude anything else. I will try to feed the pump directly from the bucket, just to eliminate installed filters hoses etc.
Hi Thank you for your feedback. I have had Sumitomo South Africa agents look at my 2 Excavators with problems in November. They claimed to want to start them from using a test ECU. So they cleared all codes and used a test ECU. There was no change. Machine starts up but revs die once you try to lift the boom. They suggested that the culprit could be a Cam or Crank sensor as that's the code repeatedly showing. However I have not done anything yet. Another advise from another technician was that the cam fault code would appear in any case if the machine is starving for fuel because of any other reason and he suggested I replace the speed switch. On the other Sumitomo the agents can't find the fault, having checked it out since when the issues started 2 years ago. However before the agents came in November, I have had the SCV haphazardly cleaned on it and refitted in 5 minutes. It worked perfectly for 1 day. After it switched off, it doesn't start. Advise from other Mechanics is to check the fuel line and replace the SCV. I will post an update once I try.
If your machine dies when you try to lift the boom, it may not be engine that is the problem. It may be hydraulic pumps control. If pumps are on max flow, they will overpower the engine for sure. Are other movements working except boom?
I got engine diagnostic and checked rail pressure. When cranking pressure rises and then as engine starts it goes up to 1400 bar approx. Then fault comes up, and pressure drops to around 630 BAR and sits like that as the engine idles. is this something normal or is there something wrong?
Getting desperate here. Today I eliminated fuel tank and filters just to exclude fuel starvation. And checked all electrical connections. Still same problem. Does anybody know expected fuel pressures for this engine?
This machine is doing my head in. I'm desperate for someone that has in depth knowlege of this engine. I have replaced commonrail pressure sensor also. And I get same error code. So far replaced, DBV valve, MPROP valve, fuel pressure sensor. Checked all electrical connections OK. Checked PWM signal from computer to MPROP, looks OK. Checked voltage from pressure sensor 2.12 VDC for 630 BAR pressure. Thing that is bugging me at the moment is that I don't have any working engine references to compare to. Like what pressure is expected at idle, and what voltage should that be from the sensor. And what PWM duty cycle vs. pressure is actuated on the MPROP valve. I can measure all this no problem, but without knowing what my target values are, a bit hopeless. Any ideas please?
Problem solved. replaced commonrail pipe, and another regulator valve. Working fine.
Can you discuss briefly please be cause i am also facing same problem,,20411 error code
Basically, if you are replacing parts, try to get exact same model numbers. I bought "direct replacement" valve with different numbers, and that didn't work for me. And check fine mesh filter inside the high pressure pump. After trying numerous other things, for me problem was solved by replacing valve with original numbers, replacing filter inside the pump, and distribution pipe.
Can you please suggest me how to solve the problem of 20411 error code
Good moring. Sorry, about the problem with the DBV VALVE. I would like to know: where is it located on the excavator? Is it part of the engine? How do I know what it is and identify it to change it? Thanks