I have a very frustrating intermittent fault which is becoming more difficult to get to the bottom of on our 28x.

call Schwing, since you have a faut code, they should be able to backtrace to whatever triggers this particular fault code 

call Schwing, since you have a faut code, they should be able to backtrace to whatever triggers this particular fault code 

Water pressure is available because the water pump turns and throws water at the outlet. It's not like a hydraulic pump in that it can run against a closed hose nozzle (for example) without over-pressurizing and causing a blowout. It has a pressure relief valve, which is what sets the water pressure maximum.

Slow or internally-bleeding hydraulic motor or circuit will cause your symptoms; so will a pressure relief valve on the water side malfunctioning or sticking open.

Start with the cheap and easy:

• I don't have the schematic, but if there are any other devices on the same oil circuit, see if they're running at the correct speed. (Could be the agitator is on the same circuit.) If any other circuit components work as expected, you can eliminate the hydraulic pump and controls from the cause. If they don't, then the pump and hydraulic system become the prime suspect. If the hydraulics work as expected, then go to the next step.

• Try raising the pressure of the water relief valve (typically a brass colored device near the water pump with a T handle and a set screw on the shaft.) If it doesn't help, turn it back down to where it was.

• Make sure no valve is half-engaged (which would also cause heat).

If all that seems good, then your water pump could be worn out. Only replacing it would say for sure. I hope this helps. Mechanics; if I forgot something, bring it up. I may have advanced CRAFT disease. (Can't Remember A F'ing Thing.)

Schwing 28X Boom Control Fault Troubleshooting

I can understand how frustrating intermittent faults can be, especially when they shut down your pump system unpredictably. Since you've already tried replacing both wireless and hardwire remotes without success, we need to look deeper into the system.

Possible Causes for Intermittent Boom Control Faults

1. Wiring/Connection Issues

   • Look for loose or corroded wires in the e-stop switches
   • Check connections in the cable powering the remote receiver
   • Inspect for corrosion in cables (especially if the pump has been washed with acid)
   • Verify ground connections for the control box

2. Voltage Drop Issues

   • When multiple boom functions are activated, voltage can drop below the threshold needed
   • Each function you activate draws more current from the circuit
   • At some point, the e-stop relay may drop out due to voltage drop, not from a bad e-stop button

3. CAN Bus Communication Issues

   • Error 194 (CAN bus-off) indicates an interrupt from one of the devices on the network
   • Check if the keypad and display are working properly

Recommended Actions

1. Contact Schwing Service at 1-888-SCHWING with your fault code information
2. Have them help backtrace whatever triggers this particular fault code
3. Open the control boxes and inspect for loose connections
4. Test for voltage drops when operating multiple functions simultaneously

Since this is intermittent and can go weeks without occurring, it's likely related to a specific condition or combination of operations that triggers the fault.

Please arrow down and take a screenshot of the other codes so we can see what is causing the boom control fault.