311b monitor problem

[RobMonk]

I just got into my excavator to change the final drive oil and as things go something else is broke.

I can start the excavator and everything works fine mechanically but the 4 red lights at the top of the monitor flash and there is an audible beeping sound.

Any ideas what this might be?

 

[Nige]

First a question. When you turn the key and the panel goes through its test sequence on do all the warning lights (13 in total in an L-shape) illiuminate..?

The 4 red lights (Action Light) plus the audible alarm indicate you have a Level 3 warning that requires immediate engine shutdown to investigate the cause.

The only thing I can see that is Level 3 is low engine oil pressure. Is the low oil pressure light also on..? It's located 2nd from top on the RH side just below the alternator charging light.

 

[RobMonk]

No lights ever come on the display. None of the warnings or gauges.

The lights above the display flash every 5-10secs with an associated beeping

 

[Nige]

Something is wrong with the monitor IMO. When you first turn on the key before starting the engine all the warning lights should light up, the 3 digital indicators should sweep full scale and then go back to whatever their reading should be, the warning lights then all go off, etc, etc. Are you saying that doesn't happen..?

 

[RobMonk]

None of that happens.

My concern is that this is computer related. If I switch on the override switch on the back of the armrest the beeping and flashing stop. Not sure if that helps in any way. In the past I have had problem with the ECM sending incorrect information to a solenoid.

I swear I fix this machine just in time to fix something else.

 

[RobMonk]

If I could be sure it was just the screen I would just keep the fuel topped up and keep running it no problem. TBH the machine is at the end of its life so while it would be nice to have the display working its not like its the end of the world.

 

[Nige]

I think we need one of our excavator experts to chime in here but to me it appears that the monitor's goofed. It must have power because the warning lights illuminate and the alarm sounds, but the fact nothing else is working is weird. The only other thing is that if signals are not coming into the monitor from the ECM (computer) and the monitor's acting in response to the lack of signal. However nothing gets away from the fact that it is dead when you first key on, it should be doing the self-test.

If you don't have an Electrical Schematic for the machine and want one drop me a PM with your machine Serial Number and your email address.

 

[RobMonk]

Is there a place to check the oil pressure? like a place to put a gauge on? I am worried that it is an issue now.

 

[Nige]

The best way would be to remove the oil pressure switch and plug into that port. It's located about midway along the engine on the LH side. See below #25

 

[RobMonk]

Any idea what size that fitting is?

 

[RobMonk]

Also I checked the fuses but I couldn't find one that stood out as the one for that display. Any idea what fuse it should be attached to?

 

[Nige]

Sorry, no. As there isn't a seal or gasket on it I suspect it could be a tapered thread something like 1/4" NPT but that's really just a WAG.