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Bomag soil stabilizer s/n 101590041070

Pep Joe

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Abuja, Nigeria
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Please I need a help on how to test voltage to the injector pump solenoids. I don't think ecm is energizing them but I want to be sure. Three out of the six injectors share a common positive and so for the other three but each with a negative supply. I want to know if I can measure the positive to ground and get battery voltage when the ignition is on. Thanks. Attached is the engine ecm schematic.IMG_20210414_203141_933.jpg
 

mg2361

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Maybe someone will correct me if I am wrong. When both positive and negative of an injector are controlled by and ECU then no, there is no basic voltage check you can perform with a multimeter. You might be able to measure a bias voltage but that is only used by the controller for self testing of the injector circuit. Bias voltage does not carry enough amps to do anything.

What specific model soil stabilizer is it? Maybe someone out there has some experience with your specific model.
 

BigWrench55

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Correct me if I'm wrong, but the injectors are pulse with modulated. And you really can't test them with your meter. In my experience if the ecm isn't firing the injectors you likely have a failed cam or crank position sensor. Again you can't test with a meter. Try unplugging one or the other and see if it will start and run. I once worked on a deutz and that was the no start problem. A failed cam position sensor. There is possibly a software update so that the engine will run when one fails. I also worked on another deutz and the ecm blocked it from running because of low fuel level.
 

Pep Joe

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Abuja, Nigeria
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Heavy equipment technician
Thanks. The model is MPH 122-2
Maybe someone will correct me if I am wrong. When both positive and negative of an injector are controlled by and ECU then no, there is no basic voltage check you can perform with a multimeter. You might be able to measure a bias voltage but that is only used by the controller for self testing of the injector circuit. Bias voltage does not carry enough amps to do anything.

What specific model soil stabilizer is it? Maybe someone out there has some experience with your specific model.
 

Pep Joe

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Joined
Mar 5, 2020
Messages
111
Location
Abuja, Nigeria
Occupation
Heavy equipment technician
Correct me if I'm wrong, but the injectors are pulse with modulated. And you really can't test them with your meter. In my experience if the ecm isn't firing the injectors you likely have a failed cam or crank position sensor. Again you can't test with a meter. Try unplugging one or the other and see if it will start and run. I once worked on a deutz and that was the no start problem. A failed cam position sensor. There is possibly a software update so that the engine will run when one fails. I also worked on another deutz and the ecm blocked it from running because of low fuel level.
Thanks sir. At first it was starting but not responding to throttle and smoking. All time on low idle and can't work with it. Engine mechanical guys opened the injectors pump and found out three out if the six injectors springs were broken. Ordered for complete six and changed them, hoping it will start fine after changing them, but now we are having no start problem. You talked about the cam and crank position sensor but we can see cranking speed when we unplugged either of them which shows the two are good. I saw 166 rpm cranking engine speed. We can see other engine parameters are okay but still not starting. Any further help sir. Attached are IMG_20210410_085156_950.jpg IMG_20210414_135625_145.jpg the change injectors spring and the engine status when checked with Deutz hslight diagnostic tool.
 

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Pep Joe

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Abuja, Nigeria
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Heavy equipment technician
I’m with MG ^
If it's Cat machine I would have done injectors solenoid test with Cat ET to know, but I don't have access on this deutz. I want to ask again because the schematic shows that three shares common positive as the other three. I was thinking maybe I can read the positive to chasis and get battery voltage and then during cranking is when it will send negative to each injectors base on the firing order. Because the technician I met there told me they measured voltage before when it was starting but not responding to throttle and smoking white. The thing is I don't know what voltage the ecm is sending, I want to be sure because they have concluded that it's electrical problem that the ecm is not supplying the positive. Thanks
 

mg2361

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Many of these newer injection systems use what is called a peak and hold strategy. In simple terms when it is ready to fire the controller supplies both voltage and ground at approximately the same time. Though it varies by manufacturer, approximately 90 volts is sent to the injector to get the pintle moving and then drops the voltage to somewhere near battery voltage to hold the injector open for the duration of injection. This all happens too fast for a multimeter to capture.

If there was an electrical problem with the injection system there would most likely be codes.
 

Pep Joe

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Mar 5, 2020
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Location
Abuja, Nigeria
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Heavy equipment technician
Many of these newer injection systems use what is called a peak and hold strategy. In simple terms when it is ready to fire the controller supplies both voltage and ground at approximately the same time. Though it varies by manufacturer, approximately 90 volts is sent to the injector to get the pintle moving and then drops the voltage to somewhere near battery voltage to hold the injector open for the duration of injection. This all happens too fast for a multimeter to capture.

If there was an electrical problem with the injection system there would most likely be codes.
True cos my senior supervisor told me exactly what you just explained. 90 volts ac or dc ? I'm keen to know. thanks
 

Pep Joe

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Abuja, Nigeria
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Heavy equipment technician
It is almost three years now. I am sorry for giving this feedback this late.

The problem of the no starting after new injector pumps that were broken were changed was "timing"

The mechanic that overhauled the engine had to drop it down again from the machine and confirmed the timing. They found out they timed it wrong. They corrected the timing.

It started one hand after that. Thanks to all who contributed on this thread even though it has been long.
 
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