This article describes how to deal with the heat in the 311B EXCAVATOR 2L cab.Control Failure
CAT Comm Adapter 3 478-0235 Diagnostics for Caterpillar
Possible Cause
1 The water valve is not installed correctly, or the valve is installed backwards. 1. If the machine is equipped with a water valve control, check the water valve to make sure it is installed correctly.
2. Some water valves have an arrow on the side of the valve body indicating the direction of water flow. Make sure the arrow points to the line leading to the heating coil.
3. If the machine is equipped with a cable-actuated water valve, make sure the cable is not wrapped around the water valve or the frame.
4. If the machine is equipped with an electric water valve, make sure the actuator is securely attached to the water valve.
Possible Cause 2
There is an electrical problem with the control panel.
1. Check the control panel to make sure that power is being supplied to the control panel after the machine is started.
2. Check to make sure that the wiring harness is connected to the control panel.
3. Check the wiring harness for any damage and exposed wires.
4. Check the circuit breaker or fuse to make sure there is no open circuit in the system.
Possible Cause 3
The water valve cable or potentiometer is faulty.
1. Determine the type of water valve control used on the machine.
2. If the water valve has a cable connected, proceed to step
3. If the machine has a built-in potentiometer, proceed to step 5. 3. Check to make sure the cable is connected to the water valve handle.
4. Check the water valve to make sure it fully opens when the temperature control knob is turned to the hottest position.
5. Check to make sure the potentiometer is connected to the wiring harness in the cab instrument panel.
6. Check the water valve to make sure it fully opens when the temperature control knob is turned to the hottest position.
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