Eng Fuel Filters Man CR900

Man's are very sensitive to shorts in alarm sensor wiring. The wires that go to the water sensor are very thin and the plug on the bowl is very fragile and could be shorting there also. What happens if you unplug that sensor, do the other alarms go away? I would probably change that plug and get rid of the bad wires (cut them back further) and solder and heatshrink then to the new water sensor/bowl assembly.)

It's those same thin wires like the fuel filter leads, that will drive you crazy.

I had a helper that could not keep his feet off of a wire harness. As forecast, it came back and bit me. Look for places that the spare oil, filters, parts or that tool box has shifted and damaged the harness. Look for foot prints and other places of vibration and chafe.

As I mentioned before, those connect stink.

I'm hoping you have ensured the big ZIF connect at the computer box is plugged in completely and locked correctly? Do this with battery OFF.

Did you pressurize the coolant (#56 above)? Any readings change?

The coolant pressure sensors have a tendancy to go bad on Man's

Is is a good suspect but I'm not blaming it. That is why I recommended a good inspection of the harness and all connects. Expressly near areas of contact, abuse and chafe.


Lets take a breath for a minute and get some history in mind.
Did all of these errors pop up at once? within a short time? After any other work?
When was the last time they worked?
Do you clear the errors off the display between test?

Errors appear on switch on? when just starting? or after some time running?

You have a MAN'nado occurring. I hope it's not getting contributed to.

Take another breath and relax, Your eyes are getting heavy, you remembering what happened just before these errors appeared, your eyes are closed now and your remembering everything now;\
Was there a lightning strike, any batteries getting crossed, battery charger sparked or did somebody accidentally poke a screwdriver where it did not belong, can you remember any hint of some induced electrical issue.

If not, step two;

Then lets get a jug of water, flashlight, lunch, pac of smokes (for me if you don't smoke), couple of old pillows or cushions, wine coolers-cold beers for later, rum for real later and find out where the wire smash, cut or bad connect is.


see #62 above.

If the computer I/O did not fry, errors wont clear, then we may have problems in the harness.

Sadly, I think that is all I can offer.

The MAN diagnostic software is licensed and regular techs usually will not have it. Not sure if that software would really test leads anyway. Maybe a loop back test,, maybe..
But you said earlier, NO MAN tech around.
Kind of curious, how far away is the closest real MAN tech?

What is your actual fuel pressure? Have you had a lot of dirty fuel issues? There is a fine mesh screen before that alarm sender and it sometimes gets dirty. I have had alarms on 1 engine cause the remote slow down to show up on the other engine.

If you're getting that reading from the MAN display, it should be above 65 psi. The 1100 common rails I run, it's between 75-86 psi. I am not 100% familiar with your engine so you'll need to look up the fuel system diagrahm on your model. On the 1100 it is right before the injector pump.